P. Valtchev, M. Hacene, and R. Missaoui. Proceedings of the 11th International Conference on Conceptual Structures (ICCS 2003), volume 2746 of Lecture Notes in Computer Science, page 282-295. Springer, (2003)
H. Schärfe, and P. Øhrstrøm. Proceedings of the 11th International Conference on Conceptual Structures (ICCS 2003), volume 2746 of Lecture Notes in Computer Science, page 201-214. Springer, (2003)
N. Oldager. Proceedings of the 11th International Conference on Conceptual Structures (ICCS 2003), volume 2746 of Lecture Notes in Computer Science, page 69-82. Springer, (2003)