A UNIFYING FORMAL ONTOLOGY MODEL - A Simple Formal Model for Unifying the Presentation of Ontologies in Semantic Web Research Topics: Knowledge Representation; Metamodeling; MetaModeling; Ontology Engineering; Ontology Sharing and Reuse; Semantic Web In Proceedings of the International Conference on Knowledge Engineering and Ontology Development - Volume 0IC3K, 327-335, 2009 , Funchal - Madeira, Portugal