public Multimap<IndexedObjectProperty, IndexedComplexPropertyChain> getNonRedundantCompositionsByLeftSubProperty() {
		return nonRedundantCompositionsByLeftSubProperty == null ? Operations
				.<IndexedObjectProperty, IndexedComplexPropertyChain> emptyMultimap()
				: nonRedundantCompositionsByLeftSubProperty;
	}
public Multimap < IndexedObjectProperty , IndexedComplexPropertyChain > getNonRedundantCompositionsByLeftSubProperty ( ) { return nonRedundantCompositionsByLeftSubProperty == null ? Operations . < IndexedObjectProperty , IndexedComplexPropertyChain > emptyMultimap ( ) : nonRedundantCompositionsByLeftSubProperty ; }
@return A {@link Multimap} from R to S such that ObjectPropertyChain(R,
root) is a subrole of S, non-redundant ones