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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="20120829073607" timestamp="2012-08-29T07:36:07Z" ns="0" title="Düsseldorf, Universitätsbibliothek D 19" />
        <page value="20120829073705" timestamp="2012-08-29T07:37:05Z" ns="0" title="Düsseldorf, Universitätsbibliothek D 35" />
        <page value="20120829073730" timestamp="2012-08-29T07:37:30Z" ns="0" title="Düsseldorf, Universitätsbibliothek, D 32" />
        <page value="20120829075350" timestamp="2012-08-29T07:53:50Z" ns="0" title="Kamper Graduale" />
        <page value="20120831095346" timestamp="2012-08-31T09:53:46Z" ns="0" title="Köln, Groß St. Martin" />
        <page value="20120913072042" timestamp="2012-09-13T07:20:42Z" ns="0" title="Verteilte Digitale Inkunabelbibliothek" />
        <page value="20120913072157" timestamp="2012-09-13T07:21:57Z" ns="0" title="E-codices - Virtuelle Handschriftenbibliothek der Schweiz" />
        <page value="20120913072226" timestamp="2012-09-13T07:22:26Z" ns="0" title="Virtuelles Skriptorium St. Matthias" />
        <page value="20120913072257" timestamp="2012-09-13T07:22:57Z" ns="0" title="Cantus Planus Regensburg" />
        <page value="20120918131225" timestamp="2012-09-18T13:12:25Z" ns="0" title="Abdinghofer Graduale" />
      </results>
    </querypage>
  </query>
</api>