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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.
See the complete documentation, or API help for more information. 
<?xml version="1.0"?>
<api>
  <query-continue>
    <querypage qpoffset="10" />
  </query-continue>
  <query>
    <querypage name="Ancientpages">
      <results>
        <page value="20070423180114" timestamp="2007-04-23T18:01:14Z" ns="0" title="Web Pages" />
        <page value="20080312163558" timestamp="2008-03-12T16:35:58Z" ns="0" title="Condensed Matter Theory" />
        <page value="20080312164455" timestamp="2008-03-12T16:44:55Z" ns="0" title="Nuclear and Particle Experiment" />
        <page value="20080312165337" timestamp="2008-03-12T16:53:37Z" ns="0" title="Particle Theory" />
        <page value="20080312173859" timestamp="2008-03-12T17:38:59Z" ns="0" title="CTP Part III Topics" />
        <page value="20080318192353" timestamp="2008-03-18T19:23:53Z" ns="0" title="Important Experiments" />
        <page value="20080320143218" timestamp="2008-03-20T14:32:18Z" ns="0" title="OPAL" />
        <page value="20080320144132" timestamp="2008-03-20T14:41:32Z" ns="0" title="Physics Topics" />
        <page value="20080321181939" timestamp="2008-03-21T18:19:39Z" ns="0" title="Hadronic Calorimetry" />
        <page value="20080327152930" timestamp="2008-03-27T15:29:30Z" ns="0" title="AMS" />
      </results>
    </querypage>
  </query>
</api>