<?xml version="1.0" encoding="UTF-8"?>
<!ELEMENT instances (instance+)>
<!ELEMENT instance (group*)>
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	id CDATA #REQUIRED
	composite CDATA #REQUIRED
	type CDATA #REQUIRED
	ref CDATA #IMPLIED
	location CDATA #IMPLIED
	alt_id CDATA #IMPLIED
>
<!ELEMENT group EMPTY>
<!ATTLIST group
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	instance CDATA #IMPLIED
>