arcroleType definition. Value MUST be a URI reference as defined in IETF RFC 2396, except if the URI shceme used is allowed to have absolute and relative forms, the URI portion MUST be absolute. The URI reference identifys some resource that describes the intended property. When no value is supplied, no particular role value is to be inferred
string
<simpleType name="arcroleType" >
<restriction base="string" />
</simpleType>