vocabulary <http://flandersmake.be/cdf/vocabulary/versioned#> as versioned {

	extends <http://flandersmake.be/cdf/vocabulary/acyclic#> as acyclic
	extends <http://flandersmake.be/cdf/vocabulary/immutable#> as immutable

	aspect Versioned :> immutable:Thing []
	
	relation entity HasParent :> acyclic:Acyclic [
		from Versioned
		to Versioned
		forward hasParent
		reverse isParentOf
		asymmetric
		irreflexive
	]
}