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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 apcontinue="Bernstein_polynomial" />
  </query-continue>
  <query>
    <allpages>
      <p pageid="5167" ns="0" title="BORV" />
      <p pageid="496" ns="0" title="Basis" />
      <p pageid="1919" ns="0" title="Basis (linear algebra)" />
      <p pageid="532" ns="0" title="Basis (topology)" />
      <p pageid="94" ns="0" title="Basis and coordinates" />
      <p pageid="1360" ns="0" title="Basis criterion (topology)" />
      <p pageid="498" ns="0" title="Basis for a topology" />
      <p pageid="1815" ns="0" title="Basis for the tensor product" />
      <p pageid="1816" ns="0" title="Basis for the tensor product/Statement" />
      <p pageid="5299" ns="0" title="Bastard&#039;s object" />
    </allpages>
  </query>
</api>