C. Vescovo, B. Parsia, and U. Sattler. Proceedings of the 19th International Conference on Conceptual Structures (ICCS 2011), volume 6828 of Lecture Notes in Computer Science, page 187-200. Springer, (2011)
C. Hoede, and L. Zhang. Proceedings of the 9th International Conference on Conceptual Structures (ICCS 2001), volume 2120 of Lecture Notes in Computer Science, page 15-28. Springer, (2001)