H. Schärfe, U. Petersen, and P. Øhrstrøm. Proceedings of the 10th International Conference on Conceptual Structures (ICCS 2002), volume 2393 of Lecture Notes in Computer Science, page 285-298. Springer, (2002)
M. May, and J. Petersen. Proceedings of the 15th International Conference on Conceptual Structures (ICCS 2007), volume 4604 of Lecture Notes in Artificial Intelligence, page 220-240. Berlin, Heidelberg, Springer-Verlag, (July 2007)
W. Petersen, and M. Werning. Proceedings of the 15th International Conference on Conceptual Structures (ICCS 2007), volume 4604 of Lecture Notes in Artificial Intelligence, page 415-428. Berlin, Heidelberg, Springer-Verlag, (July 2007)
W. Petersen. Proceedings of the 13th International Conference on Conceptual Structures (ICCS 2005), volume 3596 of Lecture Notes in Computer Science, page 337-352. Springer, (2005)