DLSafeRule(Body(BuiltInAtom(<urn:swrl:var#v1> Variable(<urn:swrl:var#var3>) Variable(<urn:swrl:var#var4>))) Head(BuiltInAtom(<urn:swrl:var#v2> Variable(<urn:swrl:var#var5>) Variable(<urn:swrl:var#var6>))))