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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.
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<?xml version="1.0"?>
<api>
  <query-continue>
    <querypage qpoffset="10" />
  </query-continue>
  <query>
    <querypage name="Ancientpages">
      <results>
        <page value="20150331142622" timestamp="2015-03-31T14:26:22Z" ns="0" title="Casos de éxito" />
        <page value="20150420100733" timestamp="2015-04-20T10:07:33Z" ns="0" title="Casos de éxito en Equipamientos Barriales" />
        <page value="20150420103823" timestamp="2015-04-20T10:38:23Z" ns="0" title="Equipamientos Barriales" />
        <page value="20150420104426" timestamp="2015-04-20T10:44:26Z" ns="0" title="Base de datos nuevos equipamientos barriales" />
        <page value="20150420120042" timestamp="2015-04-20T12:00:42Z" ns="0" title="CONTEXTOS" />
        <page value="20150516112240" timestamp="2015-05-16T11:22:40Z" ns="0" title="Servicios ecosistémicos Huertos Urbanos" />
        <page value="20150516114505" timestamp="2015-05-16T11:45:05Z" ns="0" title="Datos de análisis Huertos Urbanos" />
        <page value="20150516140439" timestamp="2015-05-16T14:04:39Z" ns="0" title="Introducción Huertos Urbanos" />
        <page value="20150518172112" timestamp="2015-05-18T17:21:12Z" ns="0" title="MARCO CONCEPTUAL" />
        <page value="20150518173751" timestamp="2015-05-18T17:37:51Z" ns="0" title="METODOLOGÍA" />
      </results>
    </querypage>
  </query>
</api>