Linuxdoc Reference
  A introduction to the linuxdoc dtd
  Uwe B�hme, <uwe@hof.baynet.de>
  v1.1, 30 January 2000

  This article is intended to be a reference for the SGML document type
  definition linuxdoc, which is coming along with the SGML text format�
  ting system version 1.0.  It should also be applicable to future ver�
  sions which may be found at My Homepage
  <http://www.hof.baynet.de/~uwe>.
  ______________________________________________________________________

  Table of Contents



  1. Making of

     1.1 Legal stuff
     1.2 Genesis

  2. Introduction

  3. A minimalistic document

     3.1 Step By Step
     3.2 A Startup Document

  4. Document Classes

     4.1 Article Tag
        4.1.1 Titlepage Tag
           4.1.1.1 Title Tag
           4.1.1.2 Author Tag
           4.1.1.3 Date Tag
           4.1.1.4 Abstract Tag
        4.1.2 Header Tag
        4.1.3 Table Of Contents Tag
        4.1.4 List Of Figures Tag
        4.1.5 List Of Tables Tag
        4.1.6 Body
        4.1.7 Appendix Tag
        4.1.8 Bibliography Tag
        4.1.9 Footnote Tag
     4.2 Report Tag
     4.3 Book Tag
     4.4 Letter Tag
     4.5 Telefax Tag
     4.6 Slides Tag
        4.6.1 Slide Tag
     4.7 Note Tag
     4.8 Manual Page Tag

  5. Inlines

  6. Sectioning

  7. Paragraphs

     7.1 Normal Paragraph
        7.1.1 Paragraph tag
        7.1.2 Empty Newline
     7.2 List-like Paragraphs
        7.2.1 List Tag
        7.2.2 Itemize Tag
        7.2.3 Enum Tag
        7.2.4 Descrip Tag
     7.3 Figures and Tables
        7.3.1 Table Tag
        7.3.2 Figure Tag
           7.3.2.1 Encapsulated Postscript(TM) Tag
           7.3.2.2 Placeholder Tag
     7.4 Tabular Tag
     7.5 Mathematical Paragraph
        7.5.1 Displayed Formula Tag
        7.5.2 Equation Tag
     7.6 Theorem Paragraph
     7.7 Code and verbatim Paragraphs
        7.7.1 Code Tag
        7.7.2 Verbatim Tag

  8. Inline Tags
     8.1 Emphasizes
     8.2 Short-quote Tag
     8.3 Formula Tag
     8.4 External Tag

  9. Mathematical Formulas

     9.1 Fraction Tag
     9.2 Product, Integral and Summation Tag
     9.3 Limited Tag
     9.4 Array Tag
     9.5 Root Tag
     9.6 Figure Tag
     9.7 Realfont Tag
     9.8 Other Mathematical Tags

  10. Labels and References

     10.1 Label Tag
     10.2 Reference Tag
     10.3 Page reference Tag
     10.4 Url Tag
     10.5 Htmlurl Tag
     10.6 Cite Tag
     10.7 Ncite Tag

  11. Indices

     11.1 Including a index
        11.1.1 Manually
        11.1.2 Hacked

  12. Literate Programming

  13. Reference

  14. Named Symbols

     14.1 Named Characters
     14.2 Named Whitespaces

  15. Mathematical Figures

  16. Linuxdoc dtd Source



  ______________________________________________________________________

  1.  Making of



  1.1.  Legal stuff

  This document may be distributed under the terms set forth in the
  Linux Documentation Project License at LDP
  <http://metalab.unc.edu/LDP/COPYRIGHT.html>.  Please contact the
  authors if you are unable to get the license.  This is free
  documentation.  It is distributed in the hope that it will be useful,
  but without any warranty; without even the implied warranty of
  merchantability or fitness for a particular purpose.

  This document is not part of form of license).  I'm not yet playing in
  that league.

  1.2.  Genesis

  This document was born trying to learn more about writing texts on my
  linux system.  The one system looking like suitable to my needs was
  sgml-tools SGML-Tools Organsation <http://www.sgml-tools.org> an the
  linuxdoc dtd.

  In [SGML-Tools User's Guide 1.0 ($Revision: 1.1.1.1 $)] (see section
  ``Reference'') the overall structure is described nice and easy.  Also
  [Quick SGML Example, v1.0] (see section ``Reference'') was helpful,
  but:

  A lot of features are not mentioned.

  On the way to learn more about it, I met [The qwertz Document Type
  Definition] (see section ``Reference'').  It's as detailed as hoped,
  but it's not made for the linuxdoc dtd

  I tried a new approach: Look at the dtd (-- dtd = document type
  definition--)

  file itself, and try to understand it.

  As time went by I noticed that I also forgot about some stuff, or - at
  least - didn't point it out strong enough.  This will change within
  the next revision.

  Any feedback you might have is welcome (especially help with English
  spelling or grammar) by e-mail at Uwe B�hme
  <mailto:uwe@hof.baynet.de>.



  2.  Introduction

  The principle of any sgml'ed document (linuxdoc, docbook, html) is
  more or less the same:

  Don't write how it should look like, but write what it is.

  This is a different approach than the standard "wysiwyg" (-- What you
  see is what you (should) get (if you are a very lucky one and your
  computer wins the war against buggy software)--) one (-- You might
  want to call it wysiwym, i.e. "What you see is what you mean"--) .
  You do not tell the program that this line should be in a bigger font,
  to look like a headline.  What you do is telling that this line is a
  headline.  You do not try to make your document look like a report,
  but you tag it to be a report.  So you tag the text with the
  appropriate <tag>.


  The big advantages of this approache are:

  1. You do not need to mess around with fontsetting, line gaps or
     anything directly connected to the layout.

  2. You describe your document in a more abstract way so it's more
     reusable and can be mapped to different media types. (-- If you
     ever tried the reuse a document written in a specialized wysiwy
     layout for html then you know what I'm talking about.--)

  In addition in all sgml-style documents you will find named symbols
  This is a concept to expand the charset of the document and to avoid
  inconsitences in decision of the parser, how to interpret or map some
  special characters.

  How should the parser know weather a < character is starting a tag or
  should be printed directly.  This is solved by the named character lt.
  If you write &lt; this one will result to < in your text.  For a list
  of the named symbols see ``Named Symbols''.


     Hint for the new user
        It might be a good idea, to download this document not only as a
        dvi or ps document, but also to download the sgml source.  This
        offers you the chance to look into the sources, if you find
        something within this article, wich might fit your needs.



  3.  A minimalistic document

  In this section you'll find what you'll need for a minimalistic
  linuxdoc dtd conform document.  It's intended to give a first touch.
  Skip this section, if you already now the principles.


  3.1.  Step By Step

  The steps you have to do to create a nice linuxdoc document and map it
  to the form you need are:


  �  Take a plain text editor of your choice.

  �  Create a file and name it (or later save it as) e.g. start.sgml.

  �  Type the document

  �  Save the file and close your editor.

  �  Run the checker by typing sgmlcheck start.sgml.

  �  If you get errors reported, reopen your document in your editor
     again and try to correct it (-- The error messages of sgmlcheck
     will give you a hint about the type of error and also line and
     column where it occurred.--) .  Run the checker again until no more
     errors occur.

  �  Now you have to decide what's your document for.  your document.
     To find the mappers available in the SGML-Tools see table ``SGML-
     Tools mappers for sgml documents''.


  type                                 to produce
  ______________________________________________________________________

  sgml2html start.sgml                 Hypertext markup language for web browsers
  sgml2lyx start.sgml                  Lyx or KLyx wysiwym textformat
  sgml2info start.sgml                 Info page for UN*X info
  sgml2latex start.sgml                DVI output
  sgml2latex --output=tex start.sgml   pure tex output
  sgml2latex --output=ps start.sgml    postscript output
  sgml2rtf start.sgml                  rich text format
  sgml2txt start.sgml                  pure text


                  SGML-Tools mappers for sgml documents



  3.2.  A Startup Document

  We start with a simple document (the numbers and colon in the
  beginning of the line are for explanation, don't type it!):


  ______________________________________________________________________
  1: <!doctype linuxdoc system>
  2: <notes>
  3: <title>A Small Linuxdoc Example</title>
  4: <p>Hello <em>world</em>.</p>
  5: <p><bf>Here</bf> we are.</p>
  6: </notes>
  ______________________________________________________________________



  Now we take a look at the single lines:

  1. A linuxdoc document has to start, like all SGML conform documents,
     with the preamble.  If you like you can take it as a piece of
     necessary magic, or you can try to find more information about
     SGML.  The preamble is indicating to the SGML-parser, which dtd
     (document type definition) it should use for checking the syntax of
     the document.

  2. Open the document class: You have to decide, wich type of document
     you want to write.  See section ``Document Classes'' for detailed
     description about that document classes.  The necessary header
     information, wich is depending on the document class is also
     explained there.  In our case we place a <notes> tag forming a
     note, wich is indicating a simple unstructured document.

  3. Even if optional it's a good idea to give a title to the document.
     That's done with the <title> tag.

  4. A paragraph marked by the <p> tag, containing the word world wich
     is inline emphasized by the <em> tag.

  5. Another completely tagged paragraph, with another word inline
     boldfaced by the <bf> tag.

  6. Here we close the open document class tag.

  The same example may be written a little bit shorter, by leaving out
  tags which are placed automatically by the parser, and by using
  shortened tags:


  ______________________________________________________________________
  1: <!doctype linuxdoc system>
  2: <notes>
  3: <title>A Small Linuxdoc Example
  4: <p>Hello <em/world/.
  5:
  6: <bf/Here/ we are.
  7: </notes>
  ______________________________________________________________________



  Now we look at the single lines again:

  1. The preambel.

  2. The document class (also unchanged).

  3. The title. It's not closed, because the p tag in the next line is
     implicitely closing it.

  4. The paragraph is implicitly closing the title. The emphasize tag is
     noted in short form. The short notation you can use only if your
     tagged text doesn't contain a litteral /. The paragraph is not
     explicitly closed in this line.

  5. The empty line here is the reason, why you don't need to close the
     previous paragraph and don't need to open the next one.  A empty
     line is interpreted as a end of the current paragraph and the start
     of a new one.

  6. Another paragraph (not opened directly), with another short inline
     tag.

  7. Closing the open document class tag, wich is implicitly also
     closing the still open paragraph.

  Maybe now it's a little bit more clear, who you have to work with
  tags.



  4.  Document Classes


  ______________________________________________________________________
  <!element linuxdoc o o
          (sect | chapt | article | report |
           book | letter | telefax | slides | notes | manpage ) >
  ______________________________________________________________________



  This is describing the overall class of the document, so naturally it
  has (leave alone the doctype definition) to be the first tag enclosing
  your whole document.  Some of the tags namely the sect and chapt (see
  section ``Sectioning Tags'') doesn't make any sense taken them
  standalone despite being included as part of more complete classed
  document, so we'll describe them later as a part of the other document
  classes.  Decide first which of the top mentioned document classes
  fits the type of the document you want to write best.

  To find a detailed description of the document classes see table
  ``Document classes''.


                       Chapter           Class tag
                       _________________________________________________

                       ``Article Tag''   <atricle>
                       ``Report Tag''    <report>
                       ``Book Tag''      <book>
                       ``Letter Tag''    <letter>
                       ``Telefax Tag''   <telefax>
                       ``Slides Tag''    <slides>
                       ``Notes Tag''     <notes>
                       ``Manpage Tag''   <manpage>


                             Document classes


  To me the article class is the most important one.  That�s the reason
  why it�s described first and most detailed.


  4.1.  Article Tag


  ______________________________________________________________________
  <!element article - -
          (titlepag, header?,
           toc?, lof?, lot?, p*, sect*,
           (appendix, sect+)?, biblio?) +(footnote)>

  <!attlist article
          opts cdata "null">
  ______________________________________________________________________


  You can see that the article needs some tags included. They will be
  explained in consequence.

  The options attribute (opts) takes a comma separated list with thy
  different style (LaTeX .sty) sheets to inlude within the document.



  4.1.1.  Titlepage Tag


  ______________________________________________________________________
  <!element titlepag o o (title, author, date?, abstract?)>
  ______________________________________________________________________


  The Titlepage Tag (titlepag) is implicitly placed as soon a you
  started your document class. You don't need to write it explicitly.
  Anyway you have to note it's mandatory tags. It's purpouse is to
  describe the layout and elements of the titlepages.



  4.1.1.1.  Title Tag


  ______________________________________________________________________
  <!element title - o (%inline, subtitle?) +(newline)>
  ______________________________________________________________________


  Each document class wich owns a titlepage of course needs a title,
  wich is noted down with a <title> tag.  You don't need to close tha�
  tone.  A title may contain a subtitle started by the <subtitle> tag.

  If you look at the headerpage of this document you'll find it to be
  mapped from the tags:


  <title>Linuxdoc Reference
  <subtitle>A introduction to the linuxdoc dtd



  4.1.1.2.  Author Tag



  ______________________________________________________________________
  <!element author - o (name, thanks?, inst?,
                          (and, name, thanks?, inst?)*)>
  ______________________________________________________________________


  Usually you place the (your) name here.  People should know who wrote
  the document, so you place a <author> tag.  If you don't note the name
  tag it�s imlicitly placed.  The author has also optional items wich
  can be tagged within the author tag.

  If you want to say thanks to anyone (might be somebody providing
  usefull information) you place it within the <thanks> tag.  Next, if
  your writing is done in your position of an institution staff member,
  place it within the <inst> tag.

  The <and> tag is starting the whole story again, as if there would be
  a second author tag would have been started.  Clearly thisone is for
  coauthors.


  4.1.1.3.  Date Tag

  If you want to mark your document with a date, you can do that with
  the <date> tag. (-- It's not checked weather you really place a valid
  date here, but don't abuse it.--)


  4.1.1.4.  Abstract Tag

  This tag is intended for an abstract description of your document.
  Don't mix the <abstract> tag withh an indruduction wich is likely to
  be placed inside the first section of your document (see section
  ``Sectioning'').



  4.1.2.  Header Tag


  ______________________________________________________________________
  <!element header - - (lhead, rhead) >
  <!element lhead - o (%inline)>
  <!element rhead - o (%inline)>
  ______________________________________________________________________


  A <header> tag specifies what should be printed at the top of each
  page.  It consists of a left heading i.e. <lhead> and a right heading
  i.e. <rhead>).  Both elements are required, if a heading is used at
  all, but either may be left empty, so that the effect of having only a
  left or right heading can be achieved easily enough.

  As we will see, an initial header can be given after the title page.
  Afterwards, a new header can be given for each new chapter or section.
  The header printed on a page is the one which is in effect at the end
  of the current page. So that the header will be that of the last
  section starting on the page.



  4.1.3.  Table Of Contents Tag

  If you place the <toc> tag, a table of contense will be generated, by
  looking the section heading, and adding references. (-- In a hyperref
  document, this might be hyperrefs, in a LaTeX document you will come
  to see the pagenumbers.--)

  Only the sections major to the sect3 will be included.



  4.1.4.  List Of Figures Tag

  If you place the <lof> tag, a list of figures will be generated, by
  looking the captions of the figures, and adding references.



  4.1.5.  List Of Tables Tag

  If you place the <lot> tag, a list of tables will be generated, by
  looking the captions of the tables, and adding references.



  4.1.6.  Body

  Here you place various sections according section ``Sectioning''.
  There is no body tag.  The body starts with the first chapter, section
  or paragraph.



  4.1.7.  Appendix Tag

  In the end of the article you can place the <appendix> tag (-- Really
  you shouldn't think about people (e.g. m.d.s knifing your belly
  here.--)

  , wich starts a area of appended sections.  The appendix tag implies a
  different section numbering type to the following section tags.


  4.1.8.  Bibliography Tag

  It's intended to gather all the <cites> and <ncites> you used within
  your document. The <biblio> tag will be replaced by a bibliography
  according the mapping type of the document, maybe by hyperrefs maybe
  by section numbers or anything wich might be useful. (-- Until now
  I've not been able to create a .bbl file, so I wasn't able to
  verify.--)



  4.1.9.  Footnote Tag

  A footnote may be place in any spot of your document.  Exactly the
  spot in yout document where you are placing the <footnote> tag should
  be the one where the reference to the tagged text shuld be rendered.
  It should be used for additional information, wich is not necessary
  for understanding the primary purpouse of yor document but might be
  usefull, interesting, or funny. (-- Whereas the last one is not always
  true, even if you try.--)

  anywhere within the article.


  4.2.  Report Tag



  ______________________________________________________________________
  <!element report - -
          (titlepag, header?, toc?, lof?, lot?, p*,
           chapt*, (appendix, chapt+)?, biblio?) +(footnote)>
  ______________________________________________________________________


  The report is a document class with a chapter oriented approach.  So
  within a document clasified by a <report> tag the toplevel is grouped
  by the <chapt> tag (see ``Sectioning''). The rest of the structure is
  identical to the article class ``Article Tag''.



  4.3.  Book Tag


  ______________________________________________________________________
  <!element book  - -
          (titlepag, header?, toc?, lof?, lot?, p*, chapt*,
           (appendix, chapt+)?, biblio?) +(footnote) >
  ______________________________________________________________________


  You will notice that the book element is identical to the report
  ``Report Tag''.  So anything valid there is also valid if you classify
  your document with a <book> tag.



  4.4.  Letter Tag


  ______________________________________________________________________
  <!entity  % addr "(address?, email?, phone?, fax?)" >

  <!element letter - -
          (from, %addr, to, %addr, cc?, subject?, sref?, rref?,
           rdate?, opening, p+, closing, encl?, ps?)>
  ______________________________________________________________________



  Also the purpose of the letter document class should be quite self
  explaining. Place a <letter> tag if you want to write one.

  The letter's tags ar described in table ``Tags in a letter''



  4.5.  Telefax Tag


  ______________________________________________________________________
  <!element telefax - -
          (from, %addr, to, address, email?,
           phone?, fax, cc?, subject?,
           opening, p+, closing, ps?)>
  ______________________________________________________________________


  Overall the structure is same to the letter class.  The only differ�
  ence is that with the <telefax> tag the receiver's <fax> tag becomes
  mandatory. (-- Should be obvious why.--)



              tag          mandatory   what's it
              __________________________________________________________

              from         yes         from sender
              address      no          sender's address
              email        no          sender's email
              phone        no          sender's phone
              fax          no          sender's fax
              to           yes         receiver
              address      no          receiver's address
              email        no          receiver's email
              phone        no          receiver's phone
              fax          no          receiver's fax
              cc           no          carbon copy
              subject      no          letters subject
              sref         no          sender's reference
              rref         no          receiver's reference
              rdate        no          received date??
              opening      yes         opening
              paragraphs   yes         see ``Paragraphs''
              closing      yes         closing
              encl         no          enclosure
              ps           no          post scriptum


                             Tags in a letter
  4.6.  Slides Tag


  ______________________________________________________________________
  <!element slides - - (slide*) >
  ______________________________________________________________________


  The slides class is intended for overhead slides and transparencies.
  So the structure of a document classified by a <slides> tag is a very
  simple one.  It contains single slide(s) startes by a <slide> tag.
  Nothing else.  If not explicitly written the first slide is started
  implicitly.


  4.6.1.  Slide Tag


  ______________________________________________________________________
  <!element slide - o (title?, p+) >
  ______________________________________________________________________


  A <slide> tag is only allowed within the slides document class.  A
  slide may contain:

  A title (see section ``The Title Tag'') and one or more paragraphs
  (see section ``Paragraphs'').  That's all.


  4.7.  Note Tag


  ______________________________________________________________________
  <!element notes - - (title?, p+) >
  ______________________________________________________________________



  Intended as a class for personal notes the structure is even more sim�
  plified than the slides document class (see ``The Slide Tag'').  After
  classifying a document with the <notes> tag only a title (see section
  ``The Title Tag'') and one or more paragraphs (see section ``Para�
  graphs'') are allowed.



  4.8.  Manual Page Tag


  ______________________________________________________________________
  <!element manpage - - (sect1*)
          -(sect2 | f | %mathpar | figure | tabular |
            table | %xref | %thrm )>
  ______________________________________________________________________


  This document class is intended for writing manual pages, fitting the
  need of the man programm.  In a document classified by a <manpage> tag
  the topleve section tag is the sect1 tag (see section ``Sectioning''),
  for easy pasting manual pages into an article or book document class.
  The exception here to the nortmal sectioning is, that there is only
  one subsection level allowed (sect2).



  5.  Inlines


  ______________________________________________________________________
  <!entity % inline
          " (#pcdata | f| x| %emph; |sq| %xref | %index | file )* " >
  ______________________________________________________________________


  Inlines may occure anywhere within the text, and doesn't have any
  influence to the textflow or logical structure of the document.


     #pcdata
        Parsed character data is just normal written text within the
        flow wich may contain other inlines.


     f  Inline mathematical formulas according to the maths.dtd. See
        ``The Formula Tag''.


     x  The external tag wich is bypassing the parser.  Tagged data
        walks directly into the mapped file.  See chapter ``The External
        Tag'' for detailed information.


     %emph;
        Emphasizes of the text. See chapter ``Emphasizes''.


     sq Shortquotes within the textflow.  See chapter ``The Short Quote
        Tad''.


     %xref
        XReferecnces within the text or external references.  See
        chapter ``Labels and References''.

     %index
        Again I can't explain this one. If you can, please mail.


     file
        Again I can't explain this one (I only could guess about picture
        files in eps).  If you can, please mail.



  6.  Sectioning


  ______________________________________________________________________
  <!element chapt - o (%sect, sect*) +(footnote)>
  <!element sect  - o (%sect, sect1*) +(footnote)>
  <!element sect1 - o (%sect, sect2*)>
  <!element sect2 - o (%sect, sect3*)>
  <!element sect3 - o (%sect, sect4*)>
  <!element sect4 - o (%sect)>
  ______________________________________________________________________


  The sectioning (-- Also the chapt tag is a sectioning tag.--) is done
  by the according elements, forming the section tree.  They are bring�
  ing the various paragraphs within our document to follow a nice tree.
  The top level tag and the allowed depth is varying with the document
  class (see section ``The Document Class'').

  The normal hierarchy is

  chapt
      sect
          sect1
              sect2
                  sect3
                      sect4



  Just take a book, look the table of conetents and you will see.

  Each of the tags out of the sectionings has nearly the same syntax.
  All of them owe a heading.  The heading tag is placed implicitly if
  you don't note it down.  Also the each of the sectioning tags may
  contain a header tag, changing the current document header (see
  section ``The Header Tag'').

  Within the you may place subordinate sections and paragraphs (see
  ``Paragraphs'').

  Some of the sectioning tags may only appear in special document
  classes (``Document Classes'').


     Hint:
        It's wise to place a label tag after the text of the section
        tag, even if you don't want to refer to the section ``Labels and
        references''.  Later when your document grows you might want to.



  7.  Paragraphs


  ______________________________________________________________________
  <!entity % sectpar
          " %par; | figure | tabular | table | %mathpar; |
            %thrm; | %litprog; ">

  <!entity % par
          "  %list; | comment | lq | quote | tscreen " >

  <!entity % litprog " code | verb " >
  ______________________________________________________________________



  Each of the here described tags form a paragraph.

  For obvious reason a paragraph is normally (-- The behaviour of the
  exceptions figure and tabular are explained there.--) starting and
  ending with a new line. (-- How else you would notice it's a paragraph
  ?--)

  There are some tags, wich always form a paragraph, and one way to form
  a paragraph implicitly.  There are various types of paragraphs,
  because not every type of paragraph is allowed to appear in every
  document class in every place.

  The different types of paragraphs are explained in the next sections.
  For more details about %litprog; see ``Literate Programming''.



  7.1.  Normal Paragraph

  Normal paragraphs can be formed in two ways:


  7.1.1.  Paragraph tag

  The <p> tag is starting a new paragraph.  This tag is mandatory if you
  want to finish a section header without explicitly closing the sect
  tag.  In this case <p> tag then closes the <sect> tag automatically.


  7.1.2.  Empty Newline

  A empty line between two paragraph is implicitly starting a new
  paragraph.  Take care within descriptive lists. There a empty <tag>
  tag will not be paragraphed by an empty line.


  7.2.  List-like Paragraphs


  ______________________________________________________________________
  <!entity % list
          " list | itemize | enum | descrip " >
  ______________________________________________________________________


  This four tags indicate the starting of a list-like paragraph.  Within
  each of the lists the single items are separated by an item tag.



  ______________________________________________________________________
  <!element item o o ((%inline; | %sectpar;)*, p*) >
  ______________________________________________________________________


  As you can see, a item may again contain paragraphs (and therefore
  also may contain other lists - even of a different type).


  7.2.1.  List Tag


  ______________________________________________________________________
  <!element list - - (item+)>
  ______________________________________________________________________



  The list tag will be mapped to a nacked list without bullets, numers
  or anything else.

  To see it, I place a small example:

  ______________________________________________________________________
  <list>
  <item>A point
  <item>Another one
  <item>Last
  </list>
  ______________________________________________________________________



  Will look (depending on the mapping) like:


  A point

  Another one

  Last


  7.2.2.  Itemize Tag


  ______________________________________________________________________
  <!element itemize - - (item+)>
  ______________________________________________________________________



  The itemize tag will be mapped to a list with bullets, wich is usually
  place for lists where the order of the items is not important.

  A small example:

  ______________________________________________________________________
  <itemize>
  <item>A point
  <item>Another one
  <item>Last
  </itemize>
  ______________________________________________________________________


  Will look (depending on the mapping) like:


  �  A point

  �  Another one

  �  Last



  7.2.3.  Enum Tag


  ______________________________________________________________________
  <!element enum - - (item+)>
  ______________________________________________________________________



  The enum tag will be mapped to a list with numbers.

  A small example:

  ______________________________________________________________________
  <enum>
  <item>A point
  <item>Another one
  <item>Last
  </enum>
  ______________________________________________________________________



  Will look (depending on the mapping) like:


  1. A point

  2. Another one

  3. Last



  7.2.4.  Descrip Tag


  ______________________________________________________________________
  <!element descrip - - (tag?, p+)+ >
  ______________________________________________________________________



  The descrip tag will be mapped to a descriptive list.  The concept
  here is a little bit different than with the other types of lists
  mentioned above.

  Here you place a tag (this time the tag's name is really litteraly
  tag) wich is described later on.



  ______________________________________________________________________
  <descrip>
  <tag/sgml/structured general markup language.
  <tag/html - hypertext markup language/
  A sgml implementation.
  It contains some concepts about linking information together in a very
  convenient way.
  This made it to be so successful and to become the standard for documents
  published by the internet.
  <tag/internet/A worldwide connected internet (internet here as a
  technical term)
  </descrip>
  ______________________________________________________________________



  Will look (depending on the mapping) like:


     sgml
        structured general markup language.

     html - hypertext markup language
        A sgml implementation. It contains some concepts about linking
        information together in a very covenient way. This made it to be
        so successfull and to become the standard for documents
        published by the internet.

     internet
        A worldwide connected internet (internet here as a technical
        term)



  7.3.  Figures and Tables

  The <figure> and the <table> tags form very special paragraphs.  Not
  always they stay within the normal textflow.  Both of the tags can
  hold a loc (loction) attribute wich is telling how to handle the flow
  of this special paragraph.

  The value of the loc attribute is a string of up to four letters,
  where each letter declares a location at which the figure or table may
  appear, as described in table ``Table Locations''.


       h   here     At the same location as in the SGML file
       t   top      At the top of a page
       b   bottom   At the bottom of a page
       p   page     On a separate page only with figures and tables


                             Table Locations

  The default value of the loc attribute is top.



  7.3.1.  Table Tag


  ______________________________________________________________________
  <!element table   - - (tabular, caption?) >
  ______________________________________________________________________


  As you can see a table consists of the <table> tag itself, including a
  <tabular> tag and a optional <caption> tag.

  The <tabular> tag may also be placed without a <table> tag so it is
  described in detail in it's own section (see ``Tabular Tag'').

  The caption is used also to place the entry for the list of tables if
  you stated one (see ``The List Of Tables Tag'').

  A short example will show how it's working together.


  <table loc="ht">
  <tabular ca="lcr">
  Look|this|table@
  Isn't|it|nice@
  1.234|mixed|columns
  </tabular>
  <caption>A sample table
  </table>



                         Look    this      table
                         Isn't    it        nice
                         1.234   mixed   columns


                              A sample table

  The caption "A sample table" would be the name in the list of tables.


  7.3.2.  Figure Tag


  ______________________________________________________________________
  <!element figure - - ((eps | ph ), img*, caption?)>
  ______________________________________________________________________


  The usage of the <figure> tag is equivalent to the <table> tag.
  Instead of the <tabular> tag you place either a <eps> or a <ph> tag.


  7.3.2.1.  Encapsulated Postscript(TM) Tag


  ______________________________________________________________________
  <!attlist eps
          file cdata #required
          height cdata "5cm"
          angle cdata "0">
  ______________________________________________________________________


  The <eps> tag is intended for including a external file in encapsu�
  lated postscript(TM) format into the document.

  The attributes of the <eps> tag are:



     file
        The file attribute needs the file name of a encapsulated
        postscript(TM) file ending with a .ps suffix.  The mandatory .ps
        suffix must not be written.


     height
        The height of the space the file is zoomed to.  If you don't
        specify it defaults to 5cm.  Take care that there's no spcae
        between the number and the length unit (i, cm).


     angle
        The angle is given in normal degrees (0-360) and as the number
        is increasing the file is rotated counter clockwise.


  A example:


  <figure loc="here">
  <eps file="logo" height="4cm" angle="15">
  <img src="logo.gif">
  <caption>A included encapsulated postscript&trade;
  </figure>



  The img tag is ignored by LaTeX-mapping and useful for html, 'cause
  most browsers don't know about eps.



               A included encapsulated postscript(TM) file.

  The caption here would go to the list of figures as decribed in
  section ``The List Of Figures Tag''.



  7.3.2.2.  Placeholder Tag


  ______________________________________________________________________
  <!attlist ph
          vspace cdata #required>
  ______________________________________________________________________


  This tag doesn't place anything but keeps a clean space for good old
  manual picture pasting.  The space kept free is destined by the vspace
  attribte.  Caveat: The numerical argument for the vspace attribte
  needs a unit directly behind the number. Don't leave a space there
  (same as for the height attribute in ``Encapsulated Postscript(TM)
  Tag''.


  <figure loc="ht">
  <ph vspace="5cm">
  <caption>A blank space.
  </figure>



  Results to:



                     A blank space for gluing a photo

  At this point you might want to look for your scissors and the glue.



  7.4.  Tabular Tag


  ______________________________________________________________________
  <!element tabular - -
         (hline?, %tabrow, (rowsep, hline?, %tabrow)*, caption?) >
  ______________________________________________________________________


  The <tabular> tag is interpreted as an own paragraph, if it is written
  standalone.  Together with a <table> tag it gets part of the paragraph
  of the <table> tag (see ``Table tag'').

  Within the tabular tag you have rows an collumns wich are separating
  the text.  You have to have at least one collumn and one row. (--
  Wouldn't be very usefull otherwise.--)

  The <tabular> tag has a mandatory ca attribute for collumn
  allignement.  The collumn allignement holds a single character for
  each collumn in their order from left to right.  The chracters you may
  place per collumn described in table ``Collumns allignements''


                             char   alignment
                             ___________________________________________

                             l      left
                             c      centered
                             r      right


                            Column alignments

  In theory you should be able to place a | into the ca attribure for
  drawing a horizontal line for separating two collumns.  The problem:
  It doesn't work.  The parser accepts it nicely, only the LaTeX output
  will map | to {$|$} wich is of course the set for four collumns with
  invalid collumn allignement for all four collums.  I'll try to figure
  out what to do about it.

  The columns within the <tabular> tag are separated by a collumn
  separator, the <colsep> tag. The character | is translated to <colsep>
  so you can also place that one instead (-- Less typing, more fun.--) .


  What's valid for collumns is also valid for rows. You separate the by
  a row separator, the <rowsep> tag.  The character @ is translated to
  <rowsep>.

  Optional you can place a horizontal line with the <hline> tag.  Take
  care with that one: The SGML tools will parse it nicely weather you
  place it in front of the row you want under the line, or behind the
  end of the row you want over it.  But the only place to write it
  without causing the parser to shout "error" is to write it dircetly
  and without space or newline behind the row separator.


  <tabular ca="lcr">
  Look|this|table@<hline>
  Isn't|it|nice@
  1.234|mixed|columns@
  </tabular>



  Results in table ``Sample table for tabular tag''


                         Look    this      table
                         _______________________________________________

                         Isn't    it        nice
                         1.234   mixed   columns


                       Sample table for tabular tag


     Attention:
        In LaTeX mapping everything works nice if you place a tabular
        tag without a table tag, only in the other mappings (e.g.  html)
        it will be messed up.


  7.5.  Mathematical Paragraph


  ______________________________________________________________________
  <!entity % mathpar " dm | eq " >
  ______________________________________________________________________



  A mathematical paragraph consits either of a displayed formula, tagged
  by <dm> (-- No, sorry, not for Deutschmark! ;-)--)

  or an equation, tagged by <eq>.  They work very much the same.

  Both of these tags contain a mathematical formula.  See ``Mathematical
  Formulas'' for the tags valid here.


     Note:
        Because neither Netscape nor Microsoft has seen any need to add
        mathematical mappings to their browsers (like demanded and
        defined by w3c), there is no nice way of mapping, or at least
        displaying the math stuff in html. So if you view the online
        version, feel free to wonder what nonsense this man is telling
        here. Might be you should take a glance at the postscript
        version.

  7.5.1.  Displayed Formula Tag

  This tag displays a mathematical formula as a paragraph.  The formula
  is mapped centered as a single line (-- No guarantee for that. You
  know: Mapping is a matter of taste.--) .


  <dm>(a+b)<sup/2/=a<sup/2/+2ab+b<sup/2/</dm>


  Is mapped to:

  (a+b) sup {2}=a sup {2}+2ab+b sup {2}



  7.5.2.  Equation Tag


  <dm>(a+b)<sup/2/=a<sup/2/+2ab+b<sup/2/</dm>


  Is mapped to:

  (a+b) sup {2}=a sup {2}+2ab+b sup {2}



  7.6.  Theorem Paragraph


  ______________________________________________________________________
  <!entity % thrm
          " def | prop | lemma | coroll | proof | theorem " >

  <!element def - - (thtag?, p+) >
  <!element prop - - (thtag?, p+) >
  <!element lemma - - (thtag?, p+) >
  <!element coroll - - (thtag?, p+) >
  <!element proof - - (p+) >
  <!element theorem - - (thtag?, p+) >
  ______________________________________________________________________


  As you can see the different types of theorem paragraphs are nearly
  identical.  The only exception wich is a little bit different is the
  proof wich doesn't own a thtag.  For all the others the thtag is giv�
  ing the tag of the theorem paragraph.

  Yust try to use that one, wich is fitting the meaning of what you are
  typing.


  <thrm>
  <thtag>Alexander's thrm</thtag>
  Let <f>&lt;fi/G/</f> be a set of non-trivially achievable subgoals
  and &mu; an order on <f>&lt;fi/G/</f>. &mu; is abstractly
  indicative if and only if it is a linearization of
  <f><lim><op>&mu;</op><ll><fi/G/</ll><ul>&ast;</ul></lim></f>.
  </theorem>



  The thrm is replaced by the adequate tag.

  Maybe somebody knowing about mathematics would be shocked about my
  abuse of the types, but I'm lazy so I simply copied the examples:

  Definition (def):

  Definition 1 (Alexander's Definition)

  Let G be a set of nontrivially achievable subgoals and u an order on
  G. u is abstractly indicative if and only if it is a linearization of
  u from {G} to {*}.


  Proposition (prop):

  Proposition 1 (Alexander's Proposition)

  Let G be a set of nontrivially achievable subgoals and u an order on
  G. u is abstractly indicative if and only if it is a linearization of
  u from {G} to {*}.


  Lemma (lemma):

  Lemma 1 (Alexander's Lemma)

  Let G be a set of nontrivially achievable subgoals and u an order on
  G. u is abstractly indicative if and only if it is a linearization of
  u from {G} to {*}.


  Corollation (coroll):

  Corolloary 1 (Alexander's Corollary)

  Let G be a set of nontrivially achievable subgoals and u an order on
  G. u is abstractly indicative if and only if it is a linearization of
  u from {G} to {*}.



  Theorem 1 (Alexander's Theorem)

  Let G be a set of nontrivially achievable subgoals and u an order on
  G. u is abstractly indicative if and only if it is a linearization of
  u from {G} to {*}.


  The proof is just the same without the thtag:


  Proof 1

  Let G be a set of nontrivially achievable subgoals and u an order on
  G. u is abstractly indicative if and only if it is a linearization of
  u from {G} to {*}.



  7.7.  Code and verbatim Paragraphs

  Both tags from a paragraph and have very similar behavior.  Inside
  this tags most special characters don't need their named form as in
  section ``Named Symbols''.  The exceptions are:

  1. &etago; -> </ -> end of tag open

     Maybe later the list will grow.

  In difference to the normal paragraph mapping white-spaces and
  newlines will be mapped literally (as you write them in your source).

  Also (with respect to manual layout) the font for mapping will be a
  non-proportional one. (-- See the difference between IIWW and IIWW.--)


     Note:
        Aggain, I'm neither a native speaker not I love mathematics a
        lot.  So I just placed some nonsense, wich might cause headache
        and grey hair for people who want to use this document for
        learning to formulate mathematical or physical theories.

        Feel free to send better examples.



  7.7.1.  Code Tag


  ______________________________________________________________________
  <!element code - - rcdata>
  ______________________________________________________________________



  Use the code tag, if you want to write sourcecode example within your
  text.

  A code sample

  <code>

  ______________________________________________________________________
  #include <stdio.h>
  int main() {
      printf("Hello world");
      return 1;
  }
  ______________________________________________________________________


  </code>


  7.7.2.  Verbatim Tag


  ______________________________________________________________________
  <!element verb - - rcdata>
  ______________________________________________________________________



  Use the verbatim tag for anything else than sourcecode (use ``Code
  Tag'' for this) which needs the good old whitespace padding, like
  terminal hardcopy, ASCII-Graphics etc.

  A verb sample

  <verb>

  /////////
  | *   * |
  |   |   |
  | <---> |
   \_____/


  </verb>


  8.  Inline Tags

  Here the abstract inlines are broken down until only true and usable
  tags will remain.  Let's recall:

  ______________________________________________________________________
  <!entity % inline
          " (#pcdata | f| x| %emph; |sq| %xref | %index | file )* " >
  ______________________________________________________________________


  Inlines don't have a influence to paragraphing, sectioning or document
  classing. Just modifying text within it's normal flow.



  8.1.  Emphasizes


  ______________________________________________________________________
  <!entity % emph
          " em|it|bf|sf|sl|tt|cparam " >
  ______________________________________________________________________



  The emphasizes are gathering the tags for emphasizing inline text.


  The different types of emphasizes are:


     em -> The Emphasize Tag
        I hate to be redundant but I have to say: The emphasize tag you
        place for emphasized text.  Normally it's mapped to italic
        letters.  So if you write <em/a emphasized text/ it will be
        mapped to a emphasized text.


     it -> The Italic Tag
        The italic tag you place for a cursive mapping. If you write
        <it/a italic text/ it will be mapped to a italic text.


     bf -> The Boldface Tag
        The boldface tag you place for a bold mapping. If you write
        <bf/a bold text/ it will be mapped to a bold text.


     sf -> The Swissfont Tag
        I know that Tom Gordon from GMD is telling that this is the sans
        serif tag.  My interpretation of the sf is swissfont wich for me
        is more easy to remember.  This is mapping the inlined text to a
        font wich is out of the helvetica family.  So <sf/a swissfont
        text/ will be mapped to a swissfont text.

     sl -> The Slanted Tag
        I think I skip the explanation. <sl/a slanted text/ will be
        mapped to a slanted text.


     tt -> The Terminaltype Tag
        Text tagged with terminaltype will be placed inline, just like
        all the other text within a paragraph. It will not be included
        into source output if you are workink as described in section
        ``Literate Programming'', even if it's looking like typed code.
        <tt/a terminal typed text/ will be mapped to a terminal typed
        text.



  8.2.  Short-quote Tag

  Normally this one could be viewed the same level like one of the
  emphasize tags, but the definition of the linuxdoc dtd is placing it
  same level like the emphasizes, and so I do.

  The shortquote tag is a inline quotation,  not forming an own
  paragraph.  The text <sq/a short quote/ is mapped to "a short quote".



  8.3.  Formula Tag

  The formula tag allows us to note down a mathematical formula within
  the normal text, not appearing in an own line. So the text
  <f>x=y<sup>2</sup></f> will be displayed as x=y sup {2}. See
  ``Mathematical Fomulas'' for the tags valid within the formula.



  8.4.  External Tag

  The external tag is passing the tagged data directly through the
  parser, without modifying it. E.g. to LaTeX.



  9.  Mathematical Formulas

  They can appear with in the tags listed in table ``Places of
  Mathematical Formulas''


           tag   description         see
           _____________________________________________________________

           f     inline formula      ``The Formula Tag''
           dm    displayed formula   ``Mathematical Paragraph''
           eq    equation            ``Mathematical Paragraph''


                     Places of Mathematical Formulas

  If you view this document mapped to html you will notice that html has
  no nice way of displaying mathematical formulas.

  After a little hand parsing the contents of a mathematical tag looks
  like:


  ______________________________________________________________________
  <!element  xx       - -
          (((fr|lim|ar|root) |
            (pr|in|sum) |
            (#pcdata|mc|(tu|phr)) |
            (rf|v|fi) |
            (unl|ovl|sup|inf))*)>
  ______________________________________________________________________


  The xx stands for f, dm or eq. All of them are the same.



     Note:
        Because neither Netscape nor Microsoft has seen any need to add
        mathematical mappings to their browsers (like demanded and
        defined by w3c), there is no nice way of mapping, or at least
        displaying the math stuff in html. So if you view the online
        version, feel free to wonder what nonsense this man is telling
        here. Might be you should take a glance at the postscript
        version.



  9.1.  Fraction Tag


  ______________________________________________________________________
  <!element  fr       - - (nu,de) >
  <!element  nu       o o ((%fbutxt;)*) >
  <!element  de       o o ((%fbutxt;)*) >
  ______________________________________________________________________



  So what we see from it is, that a fraction consits of a numerator and
  a denumerator tag, wich again each one can hold a mathematical
  formula.

  I think an example will tell you more:

  <dm><fr><nu/7/<de/13/</fr></dm>



  results to:


  {7} over {13}


  In case we want to to place � instead of the numerator without
  cleaning it up, we'll type:


  <dm><fr><nu><fr><nu/1/<de/2/</fr></nu><de/13/</fr></dm>



  Which results to:


  {{1} over {2}} over {13}


  9.2.  Product, Integral and Summation Tag


  ______________________________________________________________________
  <!element  pr       - - (ll,ul,opd?) >
  <!element  in       - - (ll,ul,opd?) >
  <!element  sum      - - (ll,ul,opd?) >
  ______________________________________________________________________



  Each of them has a lower limit (ll tag), a upper limit (ul tag) and a
  optional operand, where each of them again may consist of a formula.
  The tags are same in syntax like shown in table ``Tags with upper-,
  lower limit and operator''.


  name        example                                         result
  ______________________________________________________________________

  Product     <f>y=<pr><ll>i=1<ul>n<opd>x<inf/i/</pr></f>     y= prod  from {i=1} to {n}x sub {i}
  Integral    <f>y=<in><ll>a<ul>b<opd>x<sup/2/</in></f>       y= int  from {a} to {b}x sup {2}
  Summation   <f>y=<sum><ll>i=1<ul>n<opd>x<inf/i/</sum></f>   y= sum  from {i=1} to {n}x sub {i}


                Tags with upper-, lower limit and operator



  9.3.  Limited Tag


  ______________________________________________________________________
  <!element  lim      - - (op,ll,ul,opd?) >
  <!element  op       o o (%fcstxt;|rf|%fph;) -(tu) >
  <!element  ll       o o ((%fbutxt;)*) >
  <!element  ul       o o ((%fbutxt;)*) >
  <!element  opd      - o ((%fbutxt;)*) >
  ______________________________________________________________________



  You can use that one for operators with upper and lower limits other
  than products, sums or integrals. The for the other types defined
  operator is destinied by the optag, wich can contain again a
  mathematical formula.


  B from {i=0} to {n}x sub {i}



  9.4.  Array Tag


  ______________________________________________________________________
  <!element  ar       - - (row, (arr, row)*) >
  <!attlist  ar
      ca     cdata    #required >
  <!element  arr      - o empty >
  <!element  arc      - o empty >
  <!entity   arr "<arr>" >
  <!entity   arc "<arc>" >
  ______________________________________________________________________

  Of course a reasonable mathematical document needs a way to describe
  arrays and matrices.  The array (ar) is noted down equivalent to a
  tabular (see section ``The Tabular Tag'').  The differences in han�
  dling are:

  �  No <hline> tag.

  �  The ca attribute character | is not allowd.

  �  Columns are not separated by colsep tag but with the arc tag (array
     collumn).

  �  Rows are not separated by rowsep tag but with the arr tag (array
     row).

     Again the characters | and @ are mapped to the adequate separator
     tag, so you really can note a array same way as a tabular.


  <dm><ar ca="clcr">
  a+b+c | uv    <arc> x-y | 27    @
  a+b   | u+v   | z   | 134   <arr>
  a     | 3u+vw | xyz | 2,978
  </ar></dm>



  Is mapped to:



                     a+b+c    uv       x-y    27
                     a+b      u+v      z      134
                     a        3u+vw    xyz    2,978



  9.5.  Root Tag


  ______________________________________________________________________
  <!element  root     - - ((%fbutxt;)*) >
  <!attlist  root
          n cdata "">
  ______________________________________________________________________


  The root is noted down by the root tag, wich contains a n attribute,
  holding the value for the "n'th" root.


  <dm><root n="3"/x+y/</dm>



  is mapped to:


    sqrt {x+y}



  9.6.  Figure Tag


  ______________________________________________________________________
  <!element  fi  - o (#pcdata) >
  ______________________________________________________________________



  With the figure tag you can place mathematical figures. The tagged
  characters are directly mapped to a mathematical figure. Which
  character is mapped to which figure you'll find in ``Mathematical
  Figures''.



  9.7.  Realfont Tag


  ______________________________________________________________________
  <!element  rf  - o (#pcdata) >
  ______________________________________________________________________


  This tag is placing a real font within a mathematical formula. (-- I'm
  really not sure about rf. What should it be?--)

  No formula is allowed within that tag.


  <dm><rf/Binom:/ (a+b)<sup/2/=a<sup/2/+2ab+b<sup/2/</dm>



  is mapped to:


   bold{Binom:} (a+b) sup {2}=a sup {2}+2ab+b sup {2}



  9.8.  Other Mathematical Tags

  The remaining tags simply modify the tagged formula, without implying
  any other tag. The effect is shown in table ``Mathematical tags
  without included tags''


  name        tag   example                               result
  ______________________________________________________________________

  vector      v     <f><v/a/&times;<v/b/=<v/0/</f>   ->   {a} vec �{b} vec ={0} vec
  overline    ovl   <f><ovl/1+1/=<ovl/2/</f>         ->   {1+1} bar ={2} bar
  underline   unl   <f><unl/1+1/=<unl/2/</f>         ->   {1+1} under ={2} under
  superior    sup   <f>e=m&times;c<sup/2/</f>        ->   e=m�c sup {2}
  inferior    inf   <f>x<inf/i/:=2x<inf/i-1/+3</f>   ->   x sub {i}:=2x sub {i-1}+3


                 Mathematical tags without included tags


  10.  Labels and References



  ______________________________________________________________________
  <!entity % xref
          " label|ref|pageref|cite|url|htmlurl|ncite " >
  ______________________________________________________________________



  As soon as it�s a little bit more sophisticated a document will need
  references to other places within the document.



  10.1.  Label Tag


  ______________________________________________________________________
  <!element label - o empty>
  <!attlist label id cdata #required>
  ______________________________________________________________________


  If you want to refer to a spot, chapter or section within your docu�
  ment you place a label tag.

  A example could look like:

  ______________________________________________________________________
  <sect1>Welcome to the article<label id="intro">
  <p>...
  ______________________________________________________________________



  10.2.  Reference Tag


  ______________________________________________________________________
  <!element ref - o empty>
  <!attlist ref
          id cdata #required
          name cdata "">
  ______________________________________________________________________



  With this tag you can refer to a place within your document labeled as
  in ``Label Tag''.

  The way the reference is mapped in you document again depends to the
  mapper.  May result to a hyper-ref (HTML) or a section number (LaTeX).



  10.3.  Page reference Tag


  ______________________________________________________________________
  <!element pageref - o empty>
  <!attlist pageref
          id cdata #required>
  ______________________________________________________________________



  A example for a pageref:

  ______________________________________________________________________
  <pageref id="intro">
  ______________________________________________________________________



  In the HTML mapping there is no use for pageref, because there are no
  page numbers.  In LaTeX mapping the tag is mapped to the pagenumber of
  the reffered label.


  10.4.  Url Tag


  ______________________________________________________________________
  <!element url - o empty>
  <!attlist url
          url cdata #required
          name cdata "" >
  ______________________________________________________________________



  A example for a url:

  ______________________________________________________________________
  <url url="http://www.gnu.org" name="GNU Organization">
  ______________________________________________________________________


  GNU Organisation <http://www.gnu.org>

  The mapping to html brings up a hyper-ref in your document.  The
  reference is the value of the url attribute, the text standing in the
  Hyperref is the name attribute's value.

  In LaTeX mapping this one results to the name followed by the url.



  10.5.  Htmlurl Tag


  ______________________________________________________________________
  <!element htmlurl - o empty>
  <!attlist htmlurl
          url cdata #required
          name cdata "" >
  ______________________________________________________________________


  A example for a htmlurl:

  ______________________________________________________________________
  <htmlurl url="http://www.gnu.org" name="GNU Organization">
  ______________________________________________________________________


  GNU Organisation

  The only difference between this tag and the ``Url Tag'' is in the
  LaTeX mapping.


  The LaTeX mapping simply drops the url attribute and emphasizes the
  name.

  In all other cases it's absolutely the same as the url tag.



  10.6.  Cite Tag


  ______________________________________________________________________
  <!element cite - o empty>
  <!attlist cite
          id cdata #required>
  ______________________________________________________________________



  AFAIK this one need�s bibTeX to work nicely.  So I'm terribly sorry,
  but I was not jet able to make use of it.  For that reason for sure
  I'm the wrong one to explain about it.



  10.7.  Ncite Tag


  ______________________________________________________________________
  <!element ncite - o empty>
  <!attlist ncite
          id cdata #required
          note cdata #required>
  ______________________________________________________________________



  Same as ``Cite Tag''.


  11.  Indices


  ______________________________________________________________________
  <!entity % index "idx|cdx|nidx|ncdx" >

  <!element idx - - (#pcdata)>
  <!element cdx - - (#pcdata)>
  <!element nidx - - (#pcdata)>
  <!element ncdx - - (#pcdata)>
  ______________________________________________________________________



             tag    my translation
             ___________________________________________________________

             idx    index
             cdx    code index (terminaltype index)
             nidx   invisible index
             ncdx   invisible code index (terminaltype index)


                              Index elements


  The index tags serve for making a index of your document.  They are
  only useful if you want do do LaTeX mapping.  They only differ very
  slightly as mentioned in table ``Index elements''.


  11.1.  Including a index

  There are two ways to include indices into your document.  Look at
  both and decide.


  11.1.1.  Manually


  1. Set the opts attribute of your document class to contain the
     packages makeidx.  You do that by: <article opts="makeidx">.

  2. Mark all the words you want to be in the index later with a idx tag
     or cdx tag.  If the word you want to index to a location in your
     document is not within the text you simply write it at the location
     you want to index with the nidx tag.  It�s like the normal idx only
     the tagged text will be silently dropped in the normal document.

  3. Process your file with makeindex sgml2latex -m mydocument.sgml.
     This will produce an additional mydocument.idx.

  4. Process mydocument.idx with the makeindex command like makeindex
     mydocument.idx.
     This will produce an additional mydocument.ind.

  5. To include the now generated index in your document you process
     your document with sgml2latex -o tex -m mydocument.sgml.
     This results in output of mydocument.tex.

  6. Edit mydocument.tex with the editor of your choice.
     You look for the line \end{document} (should be somewhere close to
     the end of the file) and insert the text \printindex bevor this
     line.

  7. Process the modified file with latex mydocument.tex.
     This gives you the final mydocument.dvi wich aggain you might
     process with dvips to generate a postscript document.

     A lot of a mess, ain't it?


  11.1.2.  Hacked

  I'm currently working on a patch to the sgmltools to automate the
  inclusion and generation of a index.  To find out the current state
  see http://www.bnhof.de/~uwe/lnd/indexpatch/index.html.



  12.  Literate Programming


  ______________________________________________________________________
  <!entity % litprog " code | verb " >
  ______________________________________________________________________


  This one is a funny thing.  It's the idea of not to write some comment
  text within a program, and might be to take later some special tools,
  to extract the text (-- Think of perlpod.--) , but to write a big doc�
  ument and later to extract the code from it. (-- People who don't like
  to document their code will not appreciate.--)

  The principle is: All text within verb and code tags, will be gathered
  into a sourcefile.


  That's it, because for now I don't remember the name of the tool doing
  thatone.



  13.  Reference



  �   The qwertz Document Type Definition
     Norman Welsh

  �   SGML-Tools User's Guide 1.0 ($Revision: 1.1.1.1 $)
     Matt Welsh and Greg Hankins and Eric S. Raymond
     November 1997

  �   Quick SGML Example, v1.0
     Matt Welsh, <mdw@cs.cornell.edu>
     March 1994



  N.  Named Symbols

  N.1.  Named Characters

  This is a slightly modified list taken from [SGML-Tools User's Guide
  1.0 ($Revision: 1.1.1.1 $)]. If you miss some, don't hesitate to mail.
  A lot of the named characters shown in table ``Named Characters'' are
  same as in the html-dtd.


   AElig     �        Aacute     �              Acirc     �                 Ae     �             Agrave     �      Atilde     �
    Auml     �        Ccedil     �             Eacute     �             Egrave     �               Euml     �      Iacute     �
   Icirc     �        Igrave     �               Iuml     �             Ntilde     �             Oacute     �       Ocirc     �
      Oe     �        Ograve     �             Oslash     �               Ouml     �             Uacute     �          Ue     �
  Ugrave     �          Uuml     �             Yacute     �             aacute     �              acirc     �          ae     �
   aelig     �        agrave     �                amp     &               apos     '              aring     �         arr     {darr}
     ast     *        atilde     �               auml     �               bsol     \               bull     �      ccedil     �
     cir     O          circ     ^              clubs     {[clubs ]}     colon     :              comma     ,      commat     @
    copy     �          darr     {darr}           deg     �              diams     {[diams ]}    divide     /      dollar     $
   dquot     "        eacute     �              ecirc     �             egrave     �             equals     =       etago     </
    euml     �          excl     !             frac12     �             frac14     �             frac18     1/8    frac34     �
  frac38     3/8      frac58     5/8           frac78     7/8               gt     >               half     �      hearts     {[hearts]}
  hellip     ...      horbar     -             hyphen     -             iacute     �              icirc     �       iexcl     �
  igrave     �        iquest     �               iuml     �              laquo     �               larr     <-       lcub     {
   ldquo     ``       lowbar     _               lpar     (               lsqb     [              lsquo     `          lt     <
   mdash     --        micro     �             middot     �                 mu     u              ndash     -         not     �
  ntilde     �           num     #             oacute     �              ocirc     �                 oe     �      ograve     �
     ohm     {ohm}      ordf     �               ordm     �             oslash     �             otilde     �        ouml     �
    para     �        percnt     %             period     .               plus     +             plusmn     �       pound     �
   quest     ?          quot     "              raquo     �               rarr     ->              rcub     }       rdquo     ''
     reg     �          rpar     )               rsqb     ]              rsquo     '               sect     �        semi     ;
     sol     /        spades     {[spades]}      sup1     �               sup2     �               sup3     �          sz     �
   szlig     �         tilde     ~              times     �              trade     (TM)          uacute     �        uarr     {uarr}
   ucirc     �            ue     �             ugrave     �               uuml     �             verbar                      yacute


                             Named Characters

  N.2.  Named Whitespaces

  There is a small number of whatever you want to name it. The look like
  named characters, but will be printed not always, or not at all.


     thinsp
        Thin space:

        d&thinsp;D ->dD


     emsp
        Emphasized space: d&emsp;D -> d  D


     ensp
        Normal space: /d&ensp;D/ -> d D


     nbsp
        No break space: A spaces at wich the line is not allowed to be
        broken. Two words separated by a nbsp will be treated by parser
        and mapper to be a single long one.


     shy
        Suggest Hyphen: If the mapper is up to break a word, with has
        the shy tag inside, it will probably do the wordbreak at the
        place of the shy tag and place a hyphen instead. If no wordbreak
        is necessary the shy expands to nothging at all.


  O.  Mathematical Figures



                         center, tab(   ) ;
                         llll.
                         a-a            b-b   c-c
                         e-e            f-f   g-g
                         i-i            j-j   k-k
                         m-m            n-n   o-o
                         q-q            r-r   s-s
                         u-u            v-v   w-w
                         y-y            z-z

  |-|

                          A-A   B-B   C-C   D-D
                          E-E   F-F   G-G   H-H
                          I-I   J-J   K-K   L-L
                          M-M   N-N   O-O   P-P
                          Q-Q   R-R   S-S   T-T
                          U-U   V-V   W-W   X-X
                          Y-Y   Z-Z



                           Mathematical Figures

  The special mappings for characters you might use for building up
  mathematical figures are shown in table ``Mathematical Figures''.



  P.  Linuxdoc dtd Source

  This is the linuxdoc.dtd used to parse this document. The revision
  log, revision comments and a few redundant lines are taken out for
  saving paper and screenspace.



  ______________________________________________________________________
  <!-- This is a DTD, but will be read as -*- sgml -*-   -->
  <!-- ================================================= -->
  <!-- $Id: lnd.sgml,v 1.1.1.1 2000/03/05 14:40:31 uwe Exp $

       This is LINUXDOC96 DTD for SGML-Tools.

       This was LINUXDOC.DTD,
       a hacked version of QWERTZ.DTD v1.3 by Matt Welsh,
       Greg Hankins, Eric Raymond, Marc Baudoin and
       Tristan Debeaupuis; modified from QWERTZ.DTD by
       Tom Gordon.

  <!entity % emph
          " em|it|bf|sf|sl|tt|cparam " >

  <!entity % index "idx|cdx|nidx|ncdx" >

  <!-- url added by HG; htmlurl added by esr -->
  <!entity % xref
          " label|ref|pageref|cite|url|htmlurl|ncite " >

  <!entity % inline
          " (#pcdata | f| x| %emph; |sq| %xref | %index | file )* " >

  <!entity % list
          " list | itemize | enum | descrip " >

  <!entity % par
          "  %list; | comment | lq | quote | tscreen " >

  <!entity % mathpar " dm | eq " >

  <!entity % thrm
          " def | prop | lemma | coroll | proof | theorem " >

  <!entity % litprog " code | verb " >

  <!entity % sectpar
          " %par; | figure | tabular | table | %mathpar; |
            %thrm; | %litprog; ">
  <!element linuxdoc o o
          (sect | chapt | article | report |
           book | letter | telefax | slides | notes | manpage ) >

  <!-- `general' entity replaced with ISO entities - kwm -->
  <!entity % isoent system "isoent">
  %isoent;

  <!entity urlnam sdata "urlnam" >
  <!entity refnam sdata "refnam" >
  <!entity tex    sdata "[tex   ]" >
  <!entity latex  sdata "[latex ]" >
  <!entity latexe sdata "[latexe]" >
  <!entity tm     sdata "[trade ]" >
  <!entity dquot  sdata "[quot  ]" >
  <!entity ero    sdata "[amp   ]" >
  <!entity etago '</' >
  <!entity   Ae  '&Auml;' >
  <!entity   ae  '&auml;' >
  <!entity   Oe  '&Ouml;' >
  <!entity   oe  '&ouml;' >
  <!entity   Ue  '&Uuml;' >
  <!entity   ue  '&uuml;' >
  <!entity   sz  '&szlig;' >
  <!element  p o o (( %inline | %sectpar )+) +(newline) >
  <!entity ptag '<p>' >
  <!entity psplit '</p><p>' >

  <!shortref pmap
          "&#RS;B" null
          "&#RS;B&#RE;" psplit
          "&#RS;&#RE;" psplit
  --      '"' qtag  --
          "[" lsqb
          "~" nbsp
          "_" lowbar
          "#" num
          "%" percnt
          "^" circ
          "{" lcub
          "}" rcub
          "|" verbar >

  <!usemap pmap p>
  <!element em - - (%inline)>
  <!element bf - - (%inline)>
  <!element it - - (%inline)>
  <!element sf - - (%inline)>
  <!element sl - - (%inline)>
  <!element tt - - (%inline)>
  <!element sq - - (%inline)>
  <!element cparam - - (%inline)>

  <!entity   ftag     '<f>'    -- formula begin -- >
  <!entity   qendtag  '</sq>'>

  <!shortref sqmap
        "&#RS;B" null
  --      '"' qendtag  --
        "[" lsqb
        "~" nbsp
        "_" lowbar
        "#" num
        "%" percnt
        "^" circ
        "{" lcub
        "}" rcub
        "|" verbar >

  <!usemap   sqmap    sq >

  <!element lq - - (p*)>
  <!element quote - - ((%inline; | %sectpar;)*, p*)+ >
  <!element tscreen - - ((%inline; | %sectpar;)*, p*)+ >
  <!element itemize - - (item+)>
  <!element enum - - (item+)>
  <!element list - - (item+)>

  <!shortref desmap
          "&#RS;B" null
          "&#RS;B&#RE;" ptag
          "&#RS;&#RE;" ptag
          "~" nbsp
          "_" lowbar
          "#" num
          "%" percnt
          "^" circ
          "[" lsqb
          "]" rsqb
          "{" lcub
          "}" rcub
          "|" verbar >

  <!element descrip - - (tag?, p+)+ >
  <!usemap desmap descrip>

  <!element item o o ((%inline; | %sectpar;)*, p*) >

  <!element tag - o (%inline)>
  <!usemap desmap tag>

  <!usemap global (list,itemize,enum)>
  <!entity space " ">
  <!entity null "">

  <!--
  <!shortref bodymap
       "&#RS;B&#RE;" ptag
       "&#RS;&#RE;" ptag
        '"' qtag
        "[" lsqb
        "~" nbsp
        "_" lowbar
        "#" num
        "%" percnt
        "^" circ
        "{" lcub
        "}" rcub
        "|" verbar>
  -->

  <!element figure - - ((eps | ph ), img*, caption?)>
  <!attlist figure
          loc cdata "tbp"
          caption cdata "Caption">

  <!-- eps attributes added by mb and td  -->
  <!element eps - o empty  >
  <!attlist eps
          file cdata #required
          height cdata "5cm"
          angle cdata "0">

  <!element ph - o empty >
  <!attlist ph
          vspace cdata #required>

  <!element img - o empty>
  <!attlist img
          src cdata #required>

  <!element caption - o (%inline)>

  <!shortref oneline
       "B&#RE;" space
       "&#RS;&#RE;" null
       "&#RS;B&#RE;" null
  --      '"' qtag  --
        "[" ftag
        "~" nbsp
        "_" lowbar
        "#" num
        "%" percnt
        "^" circ
        "{" lcub
        "}" rcub
        "|" verbar>
  <!usemap oneline tag>
  <!usemap oneline caption>

  <!entity % tabrow "(%inline, (colsep, %inline)*)" >
  <!element tabular - -
         (hline?, %tabrow, (rowsep, hline?, %tabrow)*, caption?) >

  <!attlist tabular
          ca cdata #required>

  <!element rowsep - o empty>
  <!element colsep - o empty>
  <!element hline  - o empty>

  <!entity rowsep "<rowsep>">
  <!entity colsep "<colsep>">

  <!shortref tabmap
       "&#RE;" null
       "&#RS;&#RE;" null
       "&#RS;B&#RE;" null
       "&#RS;B" null
        "B&#RE;" null
        "BB"  space
        "@" rowsep
        "|" colsep
        "[" ftag
  --      '"' qtag --
        "_" thinsp
        "~" nbsp
        "#" num
        "%" percnt
        "^" circ
        "{" lcub
        "}" rcub >

  <!usemap  tabmap tabular>
  <!element table   - - (tabular, caption?) >
  <!attlist table
          loc cdata "tbp">

  <!element code - - rcdata>
  <!element verb - - rcdata>

  <!shortref ttmap     -- also on one-line --
          "B&#RE;" space
          "&#RS;&#RE;" null
          "&#RS;B&#RE;" null
          "&#RS;B" null
          '#'     num
          '%'     percnt
          '~'     tilde
          '_'     lowbar
          '^'     circ
          '{'     lcub
          '}'     rcub
          '|'     verbar >

  <!usemap ttmap  tt>
  <!element  mc  - - cdata >
  <!entity % sppos     "tu" >
  <!entity % fcs       "%sppos;|phr" >
  <!entity % fcstxt    "#pcdata|mc|%fcs;" >
  <!entity % fscs      "rf|v|fi" >
  <!entity % limits    "pr|in|sum" >
  <!entity % fbu       "fr|lim|ar|root" >
  <!entity % fph       "unl|ovl|sup|inf" >
  <!entity % fbutxt    "(%fbu;) | (%limits;) |
                        (%fcstxt;)|(%fscs;)|(%fph;)" >
  <!entity % fphtxt    "p|#pcdata" >
  <!element  f        - - ((%fbutxt;)*) >

  <!entity   fendtag  '</f>'   -- formula end -- >

  <!shortref fmap
        "&#RS;B" null
        "&#RS;B&#RE;" null
        "&#RS;&#RE;" null
        "_" thinsp
        "~" nbsp
        "]" rsqb
        "#" num
        "%" percnt
        "^" circ
        "{" lcub
        "}" rcub
        "|" verbar>

  <!usemap   fmap     f >

  <!element  dm       - - ((%fbutxt;)*)>
  <!element  eq       - - ((%fbutxt;)*)>

  <!shortref dmmap
       "&#RE;" space
        "_" thinsp
        "~" nbsp
        "]" rsqb
        "#" num
        "%" percnt
        "^" circ
        "{" lcub
        "}" rcub
        "|" verbar>

  <!usemap dmmap (dm,eq)>
  <!element  fr       - - (nu,de) >
  <!element  nu       o o ((%fbutxt;)*) >
  <!element  de       o o ((%fbutxt;)*) >
  <!element  ll       o o ((%fbutxt;)*) >
  <!element  ul       o o ((%fbutxt;)*) >
  <!element  opd      - o ((%fbutxt;)*) >
  <!element  pr       - - (ll,ul,opd?) >
  <!element  in       - - (ll,ul,opd?) >
  <!element  sum      - - (ll,ul,opd?) >
  <!element  lim      - - (op,ll,ul,opd?) >
  <!element  op       o o (%fcstxt;|rf|%fph;) -(tu) >
  <!element  root     - - ((%fbutxt;)*) >
  <!attlist  root
          n cdata "">
  <!element col o o ((%fbutxt;)*) >
  <!element row o o (col, (arc, col)*) >

  <!element  ar       - - (row, (arr, row)*) >
  <!attlist  ar
      ca     cdata    #required >
  <!element  arr      - o empty >
  <!element  arc      - o empty >
  <!entity   arr "<arr>" >
  <!entity   arc "<arc>" >

  <!shortref arrmap
       "&#RE;" space
        "@" arr
        "|" arc
        "_" thinsp
        "~" nbsp
        "#" num
        "%" percnt
        "^" circ
        "{" lcub
        "}" rcub >

  <!usemap   arrmap   ar >
  <!element  sup      - - ((%fbutxt;)*) -(tu) >
  <!element  inf      - - ((%fbutxt;)*) -(tu) >
  <!element  unl - - ((%fbutxt;)*) >
  <!element  ovl - - ((%fbutxt;)*) >
  <!element  rf  - o (#pcdata) >
  <!element  phr - o ((%fphtxt;)*) >
  <!element  v   - o ((%fcstxt;)*)
          -(tu|%limits;|%fbu;|%fph;) >
  <!element  fi  - o (#pcdata) >
  <!element  tu  - o empty >

  <!usemap global (rf,phr)>
  <!element def - - (thtag?, p+) >
  <!element prop - - (thtag?, p+) >
  <!element lemma - - (thtag?, p+) >
  <!element coroll - - (thtag?, p+) >
  <!element proof - - (p+) >
  <!element theorem - - (thtag?, p+) >
  <!element thtag - - (%inline)>

  <!usemap global (def,prop,lemma,coroll,proof,theorem)>
  <!usemap oneline thtag>
  <!entity   qtag     '<sq>' >

  <!shortref global
        "&#RS;B" null  -- delete leading blanks --
    --    '"' qtag --
        "[" ftag
        "~" nbsp
        "_" lowbar
        "#" num
        "%" percnt
        "^" circ
        "{" lcub
        "}" rcub
        "|" verbar>

  <!usemap global linuxdoc>
  <!element label - o empty>
  <!attlist label id cdata #required>

  <!-- ref modified to have an optional name field HG -->
  <!element ref - o empty>
  <!attlist ref
          id cdata #required
          name cdata "&refnam">

  <!-- url entity added to have direct url references HG -->
  <!element url - o empty>
  <!attlist url
          url cdata #required
          name cdata "&urlnam" >

  <!-- htmlurl entity added to have quieter url references esr -->
  <!element htmlurl - o empty>
  <!attlist htmlurl
          url cdata #required
          name cdata "&urlnam" >

  <!element pageref - o empty>
  <!attlist pageref
          id cdata #required>
  <!element comment - - (%inline)>
  <!element x - - ((#pcdata | mc)*) >
  <!usemap   #empty   x >

  <!-- Hacked by mdw to exclude abstract; abstract now part of titlepag -->
  <!element article - -
          (titlepag, header?,
           toc?, lof?, lot?, p*, sect*,
           (appendix, sect+)?, biblio?) +(footnote)>

  <!attlist article
          opts cdata "null">

  <!-- Hacked by mdw to exclude abstract; abstract now part of titlepag -->
  <!element report - -
          (titlepag, header?, toc?, lof?, lot?, p*,
           chapt*, (appendix, chapt+)?, biblio?) +(footnote)>

  <!attlist report
          opts cdata "null">
  <!element book  - -
          (titlepag, header?, toc?, lof?, lot?, p*, chapt*,
           (appendix, chapt+)?, biblio?) +(footnote) >

  <!attlist book
          opts cdata "null">

  <!-- Hacked by mdw, abstract now part of titlepag -->
  <!element titlepag o o (title, author, date?, abstract?)>
  <!element title - o (%inline, subtitle?) +(newline)>
  <!element subtitle - o (%inline)>
  <!usemap oneline titlepag>
  <!element author - o (name, thanks?, inst?,
                          (and, name, thanks?, inst?)*)>
  <!element name o o (%inline) +(newline)>
  <!element and - o empty>
  <!element thanks - o (%inline)>
  <!element inst - o (%inline) +(newline)>
  <!element date - o (#pcdata) >

  <!usemap global thanks>

  <!element newline - o empty >
  <!entity nl "<newline>">

  <!-- Hacked by mdw -->
  <!element abstract - o (%inline)>
  <!usemap oneline abstract>


  <!element toc - o empty>
  <!element lof - o empty>
  <!element lot - o empty>
  <!element header - - (lhead, rhead) >
  <!element lhead - o (%inline)>
  <!element rhead - o (%inline)>
  <!entity % sect "heading, header?, p* " >
  <!element heading o o (%inline)>
  <!element chapt - o (%sect, sect*) +(footnote)>
  <!element sect  - o (%sect, sect1*) +(footnote)>
  <!element sect1 - o (%sect, sect2*)>
  <!element sect2 - o (%sect, sect3*)>
  <!element sect3 - o (%sect, sect4*)>
  <!element sect4 - o (%sect)>
  <!usemap oneline (chapt,sect,sect1,sect2,sect3,sect4)>
  <!element appendix - o empty >
  <!element footnote - - (%inline)>
  <!usemap global footnote>
  <!element cite - o empty>
  <!attlist cite
          id cdata #required>

  <!element ncite - o empty>
  <!attlist ncite
          id cdata #required
          note cdata #required>

  <!element file - - (#pcdata)>

  <!element idx - - (#pcdata)>
  <!element cdx - - (#pcdata)>
  <!element nidx - - (#pcdata)>
  <!element ncdx - - (#pcdata)>

  <!element biblio - o empty>
  <!attlist biblio
          style cdata "linuxdoc"
          files cdata "">
  <!element slides - - (slide*) >

  <!attlist slides
          opts cdata "null">
  <!element slide - o (title?, p+) >
  <!entity  % addr "(address?, email?, phone?, fax?)" >

  <!element letter - -
          (from, %addr, to, %addr, cc?, subject?, sref?, rref?,
           rdate?, opening, p+, closing, encl?, ps?)>

  <!attlist letter
          opts cdata "null">

  <!element from          - o (#pcdata) >
  <!element to            - o (#pcdata) >

  <!usemap oneline (from,to)>

  <!element address       - o (#pcdata) +(newline) >
  <!element email         - o (#pcdata) >
  <!element phone         - o (#pcdata) >
  <!element fax           - o (#pcdata) >

  <!element subject       - o (%inline;) >
  <!element sref          - o (#pcdata) >
  <!element rref          - o (#pcdata) >
  <!element rdate         - o (#pcdata) >

  <!element opening       - o (%inline;) >
  <!usemap oneline opening>

  <!element closing - o (%inline;) >
  <!element cc - o (%inline;) +(newline) >
  <!element encl - o (%inline;) +(newline) >

  <!element ps - o (p+) >

  <!element telefax - -
          (from, %addr, to, address, email?,
           phone?, fax, cc?, subject?,
           opening, p+, closing, ps?)>

  <!attlist telefax
          opts cdata "null"
          length cdata "2">

  <!element notes - - (title?, p+) >
  <!attlist notes
          opts cdata "null" >
  <!element manpage - - (sect1*)
          -(sect2 | f | %mathpar | figure | tabular |
            table | %xref | %thrm )>


  <!attlist manpage
          opts cdata "null"
          title cdata ""
          sectnum cdata "1" >
  <!shortref manpage
        "&#RS;B" null
  --      '"' qtag  --
        "[" ftag
        "~" nbsp
        "_" lowbar
        "#" num
        "%" percnt
        "^" circ
        "{" lcub
        "}" rcub
        "|" verbar>

  <!usemap manpage  manpage >
  ______________________________________________________________________