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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="20070523010121" timestamp="2007-05-23T01:01:21Z" ns="0" title="CDROM Copy Protection Technology" />
        <page value="20070523012408" timestamp="2007-05-23T01:24:08Z" ns="0" title="Debian Package Management with Apt" />
        <page value="20070523012545" timestamp="2007-05-23T01:25:45Z" ns="0" title="Bash Exit Codes" />
        <page value="20070523032502" timestamp="2007-05-23T03:25:02Z" ns="0" title="Ping" />
        <page value="20070524011044" timestamp="2007-05-24T01:10:44Z" ns="0" title="Error Reporting in PHP" />
        <page value="20070524012638" timestamp="2007-05-24T01:26:38Z" ns="0" title="Logical Operators in PHP" />
        <page value="20070524013511" timestamp="2007-05-24T01:35:11Z" ns="0" title="CLI The PHP Command Line Interface" />
        <page value="20070524013730" timestamp="2007-05-24T01:37:30Z" ns="0" title="CURL Client URL Library Functions" />
        <page value="20070524014259" timestamp="2007-05-24T01:42:59Z" ns="0" title="String Functions in PHP" />
        <page value="20070524014900" timestamp="2007-05-24T01:49:00Z" ns="0" title="Control Structures in PHP" />
      </results>
    </querypage>
  </query>
</api>