F. Dau, и M. Knechtel. Proceedings of the 17th International Conference on Conceptual Structures (ICCS 2009), том 5662 из Lecture Notes in Computer Science, стр. 141-154. Springer, (2009)
S. Obiedkov, D. Kourie, и J. Eloff. Proceedings of the 14th International Conference on Conceptual Structures (ICCS 2006), том 4068 из Lecture Notes in Computer Science, стр. 374-387. Springer, (2006)