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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="20130301090346" timestamp="2013-03-01T09:03:46Z" ns="0" title="Página principal" />
        <page value="20140508164322" timestamp="2014-05-08T16:43:22Z" ns="0" title="Por qué compramos" />
        <page value="20140509154802" timestamp="2014-05-09T15:48:02Z" ns="0" title="Corteza orbitofrontal interna" />
        <page value="20140509155017" timestamp="2014-05-09T15:50:17Z" ns="0" title="Experimento eficacia advertencias cajetillas de tabaco" />
        <page value="20140509155046" timestamp="2014-05-09T15:50:46Z" ns="0" title="Experimento marcas y religión" />
        <page value="20140509155138" timestamp="2014-05-09T15:51:38Z" ns="0" title="Experimento publicidad subliminal en el tabaco" />
        <page value="20140509155203" timestamp="2014-05-09T15:52:03Z" ns="0" title="Experimento sugestión subliminal personas mayores" />
        <page value="20140509155237" timestamp="2014-05-09T15:52:37Z" ns="0" title="John Wanamaker" />
        <page value="20140509155309" timestamp="2014-05-09T15:53:09Z" ns="0" title="Neuromarketing. Neuroeconomía y negocios" />
        <page value="20140509165551" timestamp="2014-05-09T16:55:51Z" ns="0" title="Buyology" />
      </results>
    </querypage>
  </query>
</api>