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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="20151201160024" timestamp="2015-12-01T16:00:24Z" ns="0" title="Memoria de la UPI 3" />
        <page value="20160309200029" timestamp="2016-03-09T20:00:29Z" ns="0" title="Colegio Alberto Santos Buitrago - 26875500002001" />
        <page value="20160309200123" timestamp="2016-03-09T20:01:23Z" ns="0" title="UPI 2: Colegio Alberto Santos Buitrago - 26875500002001" />
        <page value="20160309200213" timestamp="2016-03-09T20:02:13Z" ns="0" title="UPI 3: Colegio Alberto Santos Buitrago - 26875500002001" />
        <page value="20160309200425" timestamp="2016-03-09T20:04:25Z" ns="0" title="UPI 4: Colegio Alberto Santos Buitrago - 26875500002001" />
        <page value="20160309200506" timestamp="2016-03-09T20:05:06Z" ns="0" title="UPI 5: Colegio Alberto Santos Buitrago - 26875500002001" />
        <page value="20160320034828" timestamp="2016-03-20T03:48:28Z" ns="0" title="Escuela Rural Páramo - 16834400013004" />
        <page value="20160320035122" timestamp="2016-03-20T03:51:22Z" ns="0" title="UPI 2: Escuela Rural Páramo - 16834400013004" />
        <page value="20160320035327" timestamp="2016-03-20T03:53:27Z" ns="0" title="UPI 3: Escuela Rural Páramo - 16834400013004" />
        <page value="20160320035550" timestamp="2016-03-20T03:55:50Z" ns="0" title="UPI 4: Escuela Rural Páramo - 16834400013004" />
      </results>
    </querypage>
  </query>
</api>