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>
    <allredirects>
      <r fromid="193" ns="0" title="Boerner, Otto Alexander" />
      <r fromid="918" ns="0" title="Fankhauser, Franz" />
      <r fromid="919" ns="0" title="Horning, Adolf Benjamin" />
      <r fromid="452" ns="0" title="Kausler, Heinrich Eduard von" />
      <r fromid="552" ns="0" title="Noyer-Weidner, Alfred Alexander Friedrich" />
      <r fromid="920" ns="0" title="Schjerve Rindler, Rosita" />
      <r fromid="914" ns="0" title="Ten Brink, Bernhard Aegidius Konrad (auch: Barend bzw. Bernard)" />
      <r fromid="921" ns="0" title="Wiese, Berthold Heinrich Friedrich" />
      <r fromid="915" ns="0" title="Wurzbach Ritter von Tannenberg, Alfred Wolfgang von" />
    </allredirects>
  </query>
</api>