G. Kokai. 7th WSEAS International Multiconference on Circuits,
Systems, Communications and Computers (WSEAS CSCC), Rethymno, Crete Island, Greece, (July 2002)
H. Juille, and J. Pollack. Proceedings of the Fifteenth National Conference on
Artificial Intelligence (AAAI-98) Tenth Conference on
Innovative Applications of Artificial Intelligence
(IAAI-98), Madison, Wisconsin, USA, AAAI Press Books, (26-30 July 1998)