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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="3" ns="0" title="MAS" />
      <p pageid="16" ns="0" title="MAS:FAQ/Q1" />
      <p pageid="13" ns="0" title="MAS:Getting Started" />
      <p pageid="138" ns="0" title="MAS System Requirements" />
      <p pageid="4" ns="0" title="MAS Template Tags" />
      <p pageid="202" ns="0" title="MPA3" />
      <p pageid="15" ns="0" title="MPA3:Admin area:Settings" />
      <p pageid="1" ns="0" title="Main Page" />
    </allpages>
  </query>
</api>