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 alcontinue="Barbe_de_Verrue/Fortunée_Briquet|1769" />
  </query-continue>
  <query>
    <alllinks>
      <l ns="0" title="Barbara Campanini/Henri Lyonnet" />
      <l ns="0" title="Barbara Diefendorf" />
      <l ns="0" title="Barbara Diefendorf" />
      <l ns="0" title="Barbe Avrillot" />
      <l ns="0" title="Barbe Avrillot" />
      <l ns="0" title="Barbe Avrillot" />
      <l ns="0" title="Barbe Avrillot/Hilarion de Coste" />
      <l ns="0" title="Barbe Cochois/Fortunée Briquet" />
      <l ns="0" title="Barbe Giroust de Morency/Fortunée Briquet" />
      <l ns="0" title="Barbe Porquini/Fortunée Briquet" />
    </alllinks>
  </query>
</api>