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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>
    <allfileusages afcontinue="CMV_RA_02_FY14_PA.pdf|31" />
  </query-continue>
  <query>
    <allfileusages>
      <f fromid="1221" ns="6" title="File:Blank Online F-VISPDAT.pdf" />
      <f fromid="1221" ns="6" title="File:Blank Online VISPDAT.pdf" />
      <f fromid="31" ns="6" title="File:BoardMembers 03 05 2013FINAL.docx" />
      <f fromid="1221" ns="6" title="File:CES One Sheet EngSpa F4518.pdf" />
      <f fromid="1221" ns="6" title="File:CES Receipt v2aFINAL11032017.pdf" />
      <f fromid="1276" ns="6" title="File:CE Discussion session v2c.ppt" />
      <f fromid="21" ns="6" title="File:CMV CoC meeting agenda 7-11-14.doc" />
      <f fromid="21" ns="6" title="File:CMV CoC meeting agenda 8-15-14.doc" />
      <f fromid="21" ns="6" title="File:CMV CoC meeting agenda 9-12-14.doc" />
      <f fromid="31" ns="6" title="File:CMV RA 02 CoC Environmental Review 2014.pdf" />
    </allfileusages>
  </query>
</api>