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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="20110525234846" timestamp="2011-05-25T23:48:46Z" ns="0" title="Ultima Racing" />
        <page value="20110602133443" timestamp="2011-06-02T13:34:43Z" ns="0" title="2009 Chinese Grand Prix" />
        <page value="20110602133652" timestamp="2011-06-02T13:36:52Z" ns="0" title="2009 Australian Grand Prix" />
        <page value="20110602134554" timestamp="2011-06-02T13:45:54Z" ns="0" title="2009 British Grand Prix" />
        <page value="20110602134815" timestamp="2011-06-02T13:48:15Z" ns="0" title="2009 South African Grand Prix" />
        <page value="20110602134853" timestamp="2011-06-02T13:48:53Z" ns="0" title="2009 Canadian Grand Prix" />
        <page value="20110602134935" timestamp="2011-06-02T13:49:35Z" ns="0" title="2009 Mexican Grand Prix" />
        <page value="20110602135102" timestamp="2011-06-02T13:51:02Z" ns="0" title="2009 Italian Grand Prix" />
        <page value="20110602135143" timestamp="2011-06-02T13:51:43Z" ns="0" title="2009 Spanish Grand Prix" />
        <page value="20110602135218" timestamp="2011-06-02T13:52:18Z" ns="0" title="2009 Belgian Grand Prix" />
      </results>
    </querypage>
  </query>
</api>