}
private Graph convertOntology(OWLOntology ontology, boolean filterTypes) throws Exception {
StringDocumentTarget output = new StringDocumentTarget();
manager.saveOntology( ontology, new TurtleOntologyFormat(), output );
Model model = ModelFactory.createDefaultModel();
model.read( new StringReader( output.toString() ), ontologyURI.toString(), "TTL" );
if( filterTypes ) {