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HTML is good for debugging, but is unsuitable for application use.
Specify the format parameter to change the output format.
To see the non HTML representation of the XML format, set format=xml.
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<?xml version="1.0"?>
<api>
  <query-continue>
    <querypage qpoffset="10" />
  </query-continue>
  <query>
    <querypage name="Ancientpages">
      <results>
        <page value="20100929174557" timestamp="2010-09-29T17:45:57Z" ns="0" title="UMBELwiki:About" />
        <page value="20100929174651" timestamp="2010-09-29T17:46:51Z" ns="0" title="UMBELwiki:Copyrights" />
        <page value="20100929190306" timestamp="2010-09-29T19:03:06Z" ns="0" title="TechWiki:Copyrights" />
        <page value="20100929190315" timestamp="2010-09-29T19:03:15Z" ns="0" title="W3C Glossary Terms" />
        <page value="20100929190323" timestamp="2010-09-29T19:03:23Z" ns="0" title="Protégé Manual" />
        <page value="20100929190332" timestamp="2010-09-29T19:03:32Z" ns="0" title="Classification of Semantic Heterogeneity" />
        <page value="20100929200534" timestamp="2010-09-29T20:05:34Z" ns="0" title="Data Definition Metadata" />
        <page value="20100929200550" timestamp="2010-09-29T20:05:50Z" ns="0" title="Syntax Highlighting" />
        <page value="20100929200551" timestamp="2010-09-29T20:05:51Z" ns="0" title="Wiki converters" />
        <page value="20100929200552" timestamp="2010-09-29T20:05:52Z" ns="0" title="Word2MediaWikiPlus" />
      </results>
    </querypage>
  </query>
</api>