<?xml version="1.0" encoding="UTF-8"?> 
<!ELEMENT IDS (elementwithid-1+, elementwithid-2+, elementwithid-3+, elementwithid-4+,elementwithid-5+,elementwithid-6+,
               elementwithidrefattr-1+,elementwithidrefattr-2+,elementwithidrefattr-3+,elementwithidrefattr-4+,elementwithidrefattr-5+,elementwithidrefattr-6+)>
<!ELEMENT elementwithid-1 (#PCDATA)>
<!ELEMENT elementwithid-2 (#PCDATA)>
<!ELEMENT elementwithid-3 (#PCDATA)>
<!ELEMENT elementwithid-4 (#PCDATA)>
<!ELEMENT elementwithid-5 (#PCDATA)>
<!ELEMENT elementwithid-6 (#PCDATA)>
<!ELEMENT elementwithidrefattr-1 (#PCDATA)>
<!ELEMENT elementwithidrefattr-2 (#PCDATA)>
<!ELEMENT elementwithidrefattr-3 (#PCDATA)>
<!ELEMENT elementwithidrefattr-4 (#PCDATA)>
<!ELEMENT elementwithidrefattr-5 (#PCDATA)>
<!ELEMENT elementwithidrefattr-6 (#PCDATA)>
<!ATTLIST elementwithid-1 anId  ID #REQUIRED>
<!ATTLIST elementwithid-2 anId  ID #REQUIRED>
<!ATTLIST elementwithid-3 anId  ID #REQUIRED>
<!ATTLIST elementwithid-4 anId  ID #REQUIRED>
<!ATTLIST elementwithid-5 anId  ID #REQUIRED>
<!ATTLIST elementwithid-6 anId  ID #REQUIRED>
<!ATTLIST elementwithidrefattr-1 anIdRef IDREF #REQUIRED>  
<!ATTLIST elementwithidrefattr-2 anIdRef IDREF #REQUIRED>
<!ATTLIST elementwithidrefattr-3 anIdRef IDREF #REQUIRED>
<!ATTLIST elementwithidrefattr-4 anIdRef IDREF #REQUIRED>
<!ATTLIST elementwithidrefattr-5 anIdRef IDREF #REQUIRED>
<!ATTLIST elementwithidrefattr-6 anIdRef IDREF #REQUIRED>