M. Goldszmidt, and J. Pearl. Proceedings of the 3rd International Conference on Principles of Knowledge Representation and Reasoning (KR'92), page 661-672. Morgan Kaufmann, (1992)
J. Pearl. Proceedings of the first international conference on Principles of knowledge representation and reasoning, page 505--516. San Francisco, CA, USA, Morgan Kaufmann Publishers Inc., (1989)
D. Dubois, and H. Prade. Proceedings of the 12th international joint conference on Artificial intelligence - Volume 1, page 419--424. San Francisco, CA, USA, Morgan Kaufmann Publishers Inc., (1991)