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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="20140606021018" timestamp="2014-06-06T02:10:18Z" ns="0" title="Data source" />
        <page value="20140606071838" timestamp="2014-06-06T07:18:38Z" ns="0" title="Sysadmin log" />
        <page value="20140606194108" timestamp="2014-06-06T19:41:08Z" ns="0" title="Book list: R programming language" />
        <page value="20140607161130" timestamp="2014-06-07T16:11:30Z" ns="0" title="Booklist: R programming language" />
        <page value="20140607161827" timestamp="2014-06-07T16:18:27Z" ns="0" title="Booklist: Python programming language" />
        <page value="20140607163202" timestamp="2014-06-07T16:32:02Z" ns="0" title="Booklist: artificial intelligence" />
        <page value="20140607164549" timestamp="2014-06-07T16:45:49Z" ns="0" title="Booklist: software development" />
        <page value="20140607170213" timestamp="2014-06-07T17:02:13Z" ns="0" title="Booklist: probability and statistics" />
        <page value="20140607170415" timestamp="2014-06-07T17:04:15Z" ns="0" title="Booklist: machine learning" />
        <page value="20140607170638" timestamp="2014-06-07T17:06:38Z" ns="0" title="Bayesian Methods for Hackers" />
      </results>
    </querypage>
  </query>
</api>