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HTML is good for debugging, but probably is not suitable for your application.
See complete documentation, or API help for more information. 
<?xml version="1.0"?>
<api>
  <query>
    <allpages>
      <p pageid="687" ns="0" title="Backup of Arena" />
      <p pageid="680" ns="0" title="Backup of Solr" />
      <p pageid="765" ns="0" title="CSS Files" />
      <p pageid="262" ns="0" title="Catalogue Record Detail" />
      <p pageid="263" ns="0" title="Catalogue search result" />
      <p pageid="301" ns="0" title="Change user name and password" />
      <p pageid="250" ns="0" title="Community guidelines" />
      <p pageid="293" ns="0" title="Create Arena account" />
      <p pageid="279" ns="0" title="Create Articles" />
      <p pageid="287" ns="0" title="Debts and payments" />
    </allpages>
  </query>
  <query-continue>
    <allpages apfrom="Dynamic I-frame" />
  </query-continue>
</api>