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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="20151012190243" timestamp="2015-10-12T19:02:43Z" ns="0" title="Greenpeace" />
        <page value="20151012190526" timestamp="2015-10-12T19:05:26Z" ns="0" title="Korporacje zawodowe" />
        <page value="20151012190640" timestamp="2015-10-12T19:06:40Z" ns="0" title="Litygacja strategiczna" />
        <page value="20151012190805" timestamp="2015-10-12T19:08:05Z" ns="0" title="Prawa obywatelskie" />
        <page value="20151012190859" timestamp="2015-10-12T19:08:59Z" ns="0" title="Opora" />
        <page value="20151012191312" timestamp="2015-10-12T19:13:12Z" ns="0" title="Proces legislacyjny" />
        <page value="20151012191411" timestamp="2015-10-12T19:14:11Z" ns="0" title="Wysłuchanie publiczne" />
        <page value="20151012192315" timestamp="2015-10-12T19:23:15Z" ns="0" title="Amnesty International" />
        <page value="20151012192430" timestamp="2015-10-12T19:24:30Z" ns="0" title="CEE Bankwatch Network" />
        <page value="20151111214241" timestamp="2015-11-11T21:42:41Z" ns="0" title="Strona główna" />
      </results>
    </querypage>
  </query>
</api>