M. Keeler. Proceedings of the 11th International Conference on Conceptual Structures (ICCS 2003), том 2746 из Lecture Notes in Computer Science, стр. 37-53. Springer, (2003)
M. Keeler. Proceedings of the 12th International Conference on Conceptual Structures (ICCS 2004), том 3127 из Lecture Notes in Computer Science, стр. 242-260. Springer, (2004)