G. Webb. Proceedings (Complement) of the Seventh European Workshop on Knowledge Acquisition for Knowledge-based Systems (EWKA'93), page 263-275. Springer-Verlag, (1993)
G. Webb, and J. Wells. Proceedings of the Eighth Australian Joint Conference on Artificial Intelligence (AI'95), page 291-298. Singapore, World Scientific, (1995)
G. Volpe, G. Singh, and D. Petrov. Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, volume 5514 of Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, page 283-292. (October 2004)