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http://www.w3.org/TR/owl-features/
2. W3C, OWL Test Results Page (March 2004),
http://www.w3.org/2003/08/owl-systems/test-results-out
3. European OntoWeb Consortium, A Survey of Ontology Tools (May 2002),
http://ontoweb.aifb.uni-karlsruhe.de/About/Deliverables/D13_v1-0.zip
4. InfoEther & BBN Technologies, SemWebCentral Validation Tools Assessment,
http://semwebcentral.org/assessment/report?type=category&category=Validation
5. Lecture Notes in Computer Science;K. Baclawski,2002