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<?xml version="1.0"?>
<api>
  <query>
    <random>
      <page id="320" ns="0" title="Dinámica de un Movimiento Unidimensional (Fiz109 DS)" />
      <page id="179" ns="0" title="Ondas Estacionarias en una Cuerda (Fiz0111)" />
    </random>
  </query>
</api>