P. Bouquet, B. Magnini, L. Serafini, и S. Zanobini. IV International and Interdisciplinary Conference on Modeling and Using Context (CONTEXT'2003), Stanford University (CA, USA), (июня 2003)
D. Randell, Z. Cui, и A. Cohn. KR'92. Principles of Knowledge Representation and Reasoning: Proceedings of the Third International Conference, Morgan Kaufmann, San Mateo, California, (1992)