?  slide 57

The same as XML


<!DOCTYPE glossary 
  PUBLIC "-//OASIS//DTD DocBook V3.1//EN">
 <glossary><title>example glossary</title>
  <GlossDiv><title>S</title>
   <GlossList>
    <GlossEntry ID="SGML" SortAs="SGML">
       <GlossTerm>Standard Generalized Markup Language</GlossTerm>
       <Acronym>SGML</Acronym>
       <Abbrev>ISO 8879:1986</Abbrev>
       <GlossDef>
            <para>A meta-markup language, used to create markup
            languages such as DocBook.</para>
            <GlossSeeAlso OtherTerm="GML">
            <GlossSeeAlso OtherTerm="XML">
       </GlossDef>
       <GlossSee OtherTerm="markup">
    </GlossEntry>
   </GlossList>
  </GlossDiv>
 </glossary>
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