<?xml version="1.0" encoding="ISO-8859-1"?>
  <!ELEMENT WilmaGraph (Cluster)>
  <!ELEMENT Cluster (ViewType?,
                     Property*,
		     LayoutEngineType?,
		     Node*,
		     Cluster*,
		     Edge*)>
  <!ELEMENT Node (ViewType?,Property*)>
  <!ATTLIST Node
    ID ID #REQUIRED>
  <!ELEMENT Edge (ViewType?,Property*)>
  <!ATTLIST Edge
    StartID IDREF #REQUIRED
    EndID IDREF #REQUIRED>
  <!ELEMENT ViewType (Property*)>
  <!ATTLIST ViewType
    Name CDATA #REQUIRED>
  <!ELEMENT LayoutEngineType (Property*)>
  <!ATTLIST LayoutEngineType 
    Name CDATA #REQUIRED>
  <!ELEMENT Property EMPTY>
  <!ATTLIST Property
    Key CDATA #REQUIRED
    Value CDATA #REQUIRED>