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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="20151201170717" timestamp="2015-12-01T17:07:17Z" ns="0" title="Institucion Educativa La Plazuela" />
        <page value="20151201182547" timestamp="2015-12-01T18:25:47Z" ns="0" title="Escuela Rural Palmira" />
        <page value="20160318204600" timestamp="2016-03-18T20:46:00Z" ns="0" title="UPI 3: Escuela Rural Cinco Mil - 26868900072202" />
        <page value="20160318205110" timestamp="2016-03-18T20:51:10Z" ns="0" title="UPI 4: Escuela Rural Cinco Mil - 26868900072202" />
        <page value="20160318205213" timestamp="2016-03-18T20:52:13Z" ns="0" title="UPI 5: Escuela Rural Cinco Mil - 26868900072202" />
        <page value="20160318210341" timestamp="2016-03-18T21:03:41Z" ns="0" title="UPI 5: Institución Educativa Palmira - 26868900086201" />
        <page value="20160318210733" timestamp="2016-03-18T21:07:33Z" ns="0" title="UPI 3: Institución Educativa La Plazuela - 26889500036401" />
        <page value="20160318211413" timestamp="2016-03-18T21:14:13Z" ns="0" title="UPI 4: Institución Educativa La Plazuela - 26889500036401" />
        <page value="20160318212227" timestamp="2016-03-18T21:22:27Z" ns="0" title="UPI 5: Institución Educativa La Plazuela - 26889500036401" />
        <page value="20160318212416" timestamp="2016-03-18T21:24:16Z" ns="0" title="UPI 4: Institución Educativa Palmira - 26868900086201" />
      </results>
    </querypage>
  </query>
</api>