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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="20110926074811" timestamp="2011-09-26T07:48:11Z" ns="0" title="Acta 23 Mayo 2011" />
        <page value="20110926075439" timestamp="2011-09-26T07:54:39Z" ns="0" title="Acta 24 Mayo 2011" />
        <page value="20110926080254" timestamp="2011-09-26T08:02:54Z" ns="0" title="Acta 21 Julio 2011" />
        <page value="20110926081018" timestamp="2011-09-26T08:10:18Z" ns="0" title="Acta 2 Junio 2011" />
        <page value="20110926083349" timestamp="2011-09-26T08:33:49Z" ns="0" title="Acta 29 Mayo 2011" />
        <page value="20110926175612" timestamp="2011-09-26T17:56:12Z" ns="0" title="Barrios: Acta 2 Junio 2011" />
        <page value="20110926181656" timestamp="2011-09-26T18:16:56Z" ns="0" title="Barrios: Acta 15 Junio 2011" />
        <page value="20110926181842" timestamp="2011-09-26T18:18:42Z" ns="0" title="Barrios: 8 Junio 2011" />
        <page value="20110926181939" timestamp="2011-09-26T18:19:39Z" ns="0" title="Barrios: Acta 8 Junio 2011" />
        <page value="20110927221411" timestamp="2011-09-27T22:14:11Z" ns="0" title="Acta 22 Septiembre 2011" />
      </results>
    </querypage>
  </query>
</api>