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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>
    <querypage name="Ancientpages">
      <results>
        <page value="20141119224744" timestamp="2014-11-19T22:47:44Z" ns="0" title="Cahier des charges : grandeurs physiques, vecteurs, gyreurs" />
        <page value="20141119224921" timestamp="2014-11-19T22:49:21Z" ns="0" title="Les grandeurs physiques" />
        <page value="20141119225708" timestamp="2014-11-19T22:57:08Z" ns="0" title="Accélération de Coriolis et inertie" />
        <page value="20141119225928" timestamp="2014-11-19T22:59:28Z" ns="0" title="Piste d&#039;essais" />
        <page value="20141119230120" timestamp="2014-11-19T23:01:20Z" ns="0" title="Aide" />
        <page value="20141120100150" timestamp="2014-11-20T10:01:50Z" ns="0" title="Calcul des coordonnées de gyreur vitesse angulaire" />
        <page value="20161030114702" timestamp="2016-10-30T11:47:02Z" ns="0" title="Les quart-de-tours entre vecteurs : gyreurs" />
        <page value="20161030115042" timestamp="2016-10-30T11:50:42Z" ns="0" title="Main Page" />
        <page value="20161030115128" timestamp="2016-10-30T11:51:28Z" ns="0" title="Métrique des grandeurs vectorielles en physique" />
        <page value="20161030115344" timestamp="2016-10-30T11:53:44Z" ns="0" title="Vecteurs, définition, propriétés" />
      </results>
    </querypage>
  </query>
</api>