1. IBM Integrated Ontology Development Toolkit (IODT),
http://www.alphaworks.ibm.com/tech/semanticstk
2. The Semantic Web Portal Project,
http://sw-portal.deri.org
3. J. Domingue, “Tadzebao and Webonto: Discussing, browsing, and editing ontologies on the web”, Proc. of the 11th Knowledge Acquisition for Knowledge-Based Systems Workshop, Apr 1998.
4. A. Farquhar, R. Fikes, and J. Rice, “The Ontolingua Server: A tool for collaborative ontology construction,” International Journal of Human-Computer Studies, Vol. 46, Issue 6, pp. 707–727, Jun 1997.
5. The DARPA Agent Markup Language (DAML),
http://www.daml.org