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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="20141202132350" timestamp="2014-12-02T13:23:50Z" ns="0" title="Viaje al centro de la tierra" />
        <page value="20141202134315" timestamp="2014-12-02T13:43:15Z" ns="0" title="Marianela" />
        <page value="20150108092523" timestamp="2015-01-08T09:25:23Z" ns="0" title="1984" />
        <page value="20150108095026" timestamp="2015-01-08T09:50:26Z" ns="0" title="Romeo y Julieta" />
        <page value="20150108142632" timestamp="2015-01-08T14:26:32Z" ns="0" title="Las lágrimas de Shiva" />
        <page value="20150108144802" timestamp="2015-01-08T14:48:02Z" ns="0" title="Enrique Jardiel Poncela" />
        <page value="20150108144956" timestamp="2015-01-08T14:49:56Z" ns="0" title="Cuatro corazones con freno y marcha atrás" />
        <page value="20150109095033" timestamp="2015-01-09T09:50:33Z" ns="0" title="De parte de la princesa muerta" />
        <page value="20150109095822" timestamp="2015-01-09T09:58:22Z" ns="0" title="Juventud en Éxtasis" />
        <page value="20150109103057" timestamp="2015-01-09T10:30:57Z" ns="0" title="Los hombres son de Marte y las mujeres son de Venus" />
      </results>
    </querypage>
  </query>
</api>