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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="20070420120402" timestamp="2007-04-20T12:04:02Z" ns="4" title="scienceamusante.net:Avertissements généraux" />
        <page value="20070515192309" timestamp="2007-05-15T19:23:09Z" ns="14" title="Catégorie:Magnétisme" />
        <page value="20070515192317" timestamp="2007-05-15T19:23:17Z" ns="14" title="Catégorie:Ondes sonores" />
        <page value="20070515192327" timestamp="2007-05-15T19:23:27Z" ns="14" title="Catégorie:Ondes électromagnétiques" />
        <page value="20071111211317" timestamp="2007-11-11T21:13:17Z" ns="0" title="CO2" />
        <page value="20080203134616" timestamp="2008-02-03T13:46:16Z" ns="0" title="C7H8N4O2" />
        <page value="20080203134645" timestamp="2008-02-03T13:46:45Z" ns="0" title="NH3" />
        <page value="20080410195632" timestamp="2008-04-10T19:56:32Z" ns="0" title="Phosphore" />
        <page value="20080421192836" timestamp="2008-04-21T19:28:36Z" ns="0" title="Vendeurs de matériel et produits" />
        <page value="20080504205215" timestamp="2008-05-04T20:52:15Z" ns="14" title="Catégorie:Indicateur coloré" />
      </results>
    </querypage>
  </query>
</api>