@prefix owl:  <http://www.w3.org/2002/07/owl#> .
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
@prefix swrl:  <http://www.w3.org/2003/11/swrl#> .
@prefix : <http://www.cs.man.ac.uk/~bparsia/2007/examples/dl-safe-ancestor.owl#> .

<http://www.cs.man.ac.uk/~bparsia/2007/examples/dl-safe-ancestor.owl> a owl:Ontology .

:mary a owl:Thing.
:sheevah a owl:Thing.
:akane a owl:Thing.
:mary :ancestorOf :sheevah.
:sheevah :ancestorOf :akane.
:akane a :AncestorOfACreep.

:Creep a owl:Class.

:AncestorOfAkane  a owl:Class;
	 owl:equivalentClass [a owl:Restriction;
        	owl:onProperty :ancestorOf;
	        owl:hasValue :akane].

:AncestorOfACreep a owl:Class;
	owl:equivalentClass [a owl:Restriction;
        	owl:onProperty :ancestorOf;
	        owl:someValuesFrom :Creep].

:ancestorOf a owl:ObjectProperty .

:x a swrl:Variable .
:y a swrl:Variable .
:z a swrl:Variable .

:theDLSafeAncestoralRule a swrl:Imp;
  swrl:body (
    [ a swrl:IndividualPropertyAtom;
      swrl:propertyPredicate :ancestorOf;
      swrl:argument1 :x;
      swrl:argument2 :y;
      ]
    [ a swrl:IndividualPropertyAtom;
      swrl:propertyPredicate :ancestorOf;
      swrl:argument1 :y;
      swrl:argument2 :z;
    ] );
  swrl:head (
    [ a swrl:IndividualPropertyAtom;
      swrl:propertyPredicate :ancestorOf;
      swrl:argument1 :x;
      swrl:argument2 :z; 
      ] ).