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HTML is good for debugging, but is unsuitable for application use.
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To see the non HTML representation of the XML format, set format=xml.
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<?xml version="1.0"?>
<api>
  <query-continue>
    <allimages aicontinue="Barabara.jpg" />
  </query-continue>
  <query>
    <allimages>
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      <img name="BLOCCO_SERVIZI.pdf" timestamp="2010-04-23T08:39:36Z" url="https://wiki.sissa.it/students/images/f/f0/BLOCCO_SERVIZI.pdf" descriptionurl="https://wiki.sissa.it/students/index.php/File:BLOCCO_SERVIZI.pdf" ns="6" title="File:BLOCCO SERVIZI.pdf" />
      <img name="Bando_150_ore_2014-15_-_English-1.pdf" timestamp="2014-10-27T17:20:11Z" url="https://wiki.sissa.it/students/images/a/af/Bando_150_ore_2014-15_-_English-1.pdf" descriptionurl="https://wiki.sissa.it/students/index.php/File:Bando_150_ore_2014-15_-_English-1.pdf" ns="6" title="File:Bando 150 ore 2014-15 - English-1.pdf" />
      <img name="Bando_Premio_Tesi_2013.pdf" timestamp="2013-07-11T07:38:42Z" url="https://wiki.sissa.it/students/images/0/09/Bando_Premio_Tesi_2013.pdf" descriptionurl="https://wiki.sissa.it/students/index.php/File:Bando_Premio_Tesi_2013.pdf" ns="6" title="File:Bando Premio Tesi 2013.pdf" />
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      <img name="Bando_Premio_Tesi_English_2013.pdf" timestamp="2013-07-11T07:43:31Z" url="https://wiki.sissa.it/students/images/9/9c/Bando_Premio_Tesi_English_2013.pdf" descriptionurl="https://wiki.sissa.it/students/index.php/File:Bando_Premio_Tesi_English_2013.pdf" ns="6" title="File:Bando Premio Tesi English 2013.pdf" />
      <img name="Bando_Tesi_Dottorato_English_2014.pdf" timestamp="2014-06-30T08:07:52Z" url="https://wiki.sissa.it/students/images/f/fc/Bando_Tesi_Dottorato_English_2014.pdf" descriptionurl="https://wiki.sissa.it/students/index.php/File:Bando_Tesi_Dottorato_English_2014.pdf" ns="6" title="File:Bando Tesi Dottorato English 2014.pdf" />
      <img name="Bando_Tesi_Dottorato_English_2015.pdf" timestamp="2015-06-22T12:57:05Z" url="https://wiki.sissa.it/students/images/a/a8/Bando_Tesi_Dottorato_English_2015.pdf" descriptionurl="https://wiki.sissa.it/students/index.php/File:Bando_Tesi_Dottorato_English_2015.pdf" ns="6" title="File:Bando Tesi Dottorato English 2015.pdf" />
    </allimages>
  </query>
</api>