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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>
    <allpages gapcontinue="The_Joint_BioEnergy_Institute" />
  </query-continue>
  <query>
    <pages>
      <page pageid="74" ns="0" title="TAM receptor regulation of the innate immune response" touched="2009-07-06T20:58:27Z" lastrevid="511" counter="1146" length="28" new="" />
      <page pageid="113" ns="0" title="The Art and Science of Systems Biology" touched="2010-09-22T21:12:52Z" lastrevid="994" counter="344002" length="10256" />
      <page pageid="14" ns="0" title="The Energetics and Mechanistic Roles of Protein Conformational Dynamics" touched="2008-10-02T23:51:44Z" lastrevid="216" counter="283106" length="2065" />
      <page pageid="56" ns="0" title="The Flagellar Length Control System" touched="2009-04-27T23:08:44Z" lastrevid="427" counter="279756" length="965" new="" />
    </pages>
  </query>
</api>