You are looking at the HTML representation of the XML format.
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>
    <alllinks galcontinue="BELTRÁN_POVEDA,_ALEJANDRO|44068" />
  </query-continue>
  <query>
    <pages>
      <page pageid="1" ns="0" title="Página principal" />
      <page pageid="2766" ns="0" title="LUCÍA DÍAZ CASCO" />
      <page pageid="3264" ns="0" title="OLIVO LÓPEZ,JORGE" />
      <page pageid="3282" ns="0" title="FM" />
      <page pageid="3688" ns="0" title="BROTINI GÓMEZ, CARLOS" />
      <page pageid="3711" ns="0" title="AYCART FERRANDO, ÁLVARO" />
      <page pageid="3729" ns="0" title="VICENTE MENASALVAS, FRANCISCO" />
      <page pageid="3736" ns="0" title="CANDELA BALBOTEO, MARIO" />
      <page pageid="43979" ns="0" title="LARRAZ GONZÁLEZ, MARTINA" />
    </pages>
  </query>
</api>