Resource sourceRes = metaModel.createResource(source.getURIRef());
ResIterator assertions = metaModel.listSubjectsWithProperty(
METAMODEL.asserter, sourceRes);
Set<NamedNode> result = new HashSet<NamedNode>();
while (assertions.hasNext()) {
Resource assertion = assertions.nextResource();
Literal assertionTimeLit = assertion.getProperty(
METAMODEL.assertionTime).getLiteral();
Resource assertedComponent = assertion.getProperty(
METAMODEL.assertedComponent).getResource();
if (!assertedComponent.hasProperty(RDF.type, type)) {