1. Berners-Lee, T., Hendler, J., Lassila, O.: The Semantic WEB. Scientific American (2001)
2. Davies, J., Fensel, D., Harmelen, F. (eds.): Towards the Semantic WEB: Ontology-driven Knowledge Management. John Wiley & Sons Ltd., England (2002)
3. Hayes, P.: Resource Description Framework (RDF): Semantics, W3C Recommendation (2004), http://www.w3.org/TR/2004/REC-rdf-mt-20040210/#rdf_entail
4. Smith, M.K., Welty, C., McGuinness, D.L.: OWL Web Ontology language Guide (2004), http://www.w3.org/TR/owl-guide/
5. Patel-Schneider, P.F., Hayes, P., Horrocks, I.: OWL Web Ontology Language Semantics and Abstract Syntax (2004), http://www.w3.org/TR/owl-semantics/