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To see the non HTML representation of the XML format, set format=xml.
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<?xml version="1.0"?>
    <categorymembers cmcontinue="page|414e475354524f4d|27959" />
      <cm pageid="125425" ns="0" title="A Brief History of Time" />
      <cm pageid="3832" ns="0" title="Absorption" />
      <cm pageid="109186" ns="0" title="Absorption Spectrum" />
      <cm pageid="4434" ns="0" title="Acceleration" />
      <cm pageid="48216" ns="0" title="Activated shelf life" />
      <cm pageid="12160" ns="0" title="AdS/CFT Correspondence" />
      <cm pageid="115027" ns="0" title="Agrophysics" />
      <cm pageid="96871" ns="0" title="Aliasing" />
      <cm pageid="51299" ns="0" title="Alpha particle" />
      <cm pageid="4457" ns="0" title="Amplitude" />