A. Kabbaj, K. Bouzouba, K. Hachimi, and N. Ourdani. Proceedings of the 14th International Conference on Conceptual Structures (ICCS 2006), volume 4068 of Lecture Notes in Computer Science, page 300-313. Springer, (2006)
A. Kabbaj. Proceedings of the 14th International Conference on Conceptual Structures (ICCS 2006), volume 4068 of Lecture Notes in Computer Science, page 286-299. Springer, (2006)