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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-continue>
    <allimages gaicontinue="4_Model_Selection.pdf" />
  </query-continue>
  <query>
    <pages>
      <page pageid="100" ns="6" title="File:0 Intro Multivariate Statistics.pdf" />
      <page pageid="109" ns="6" title="File:0b Outliers Detection.pdf" />
      <page pageid="88" ns="6" title="File:1 Outliers BMI.xlsx" />
      <page pageid="101" ns="6" title="File:1 Statistical Hypothesis Testing.pdf" />
      <page pageid="63" ns="6" title="File:2.Architettura calcolatoreV1.1.pptx" />
      <page pageid="89" ns="6" title="File:2 CurveROC BMI.xlsx" />
      <page pageid="102" ns="6" title="File:2 Machine Learning Basics.pdf" />
      <page pageid="90" ns="6" title="File:3 Costruzione Onda Quadra Armoniche.xlsx" />
      <page pageid="103" ns="6" title="File:3 Regression.pdf" />
      <page pageid="91" ns="6" title="File:4 Filtraggio di Segnali.xlsx" />
    </pages>
  </query>
</api>