S. Rudolph, M. Krötzsch, and P. Hitzler. Proceedings of the 15th International Conference on Conceptual Structures (ICCS 2007), volume 4604 of Lecture Notes in Artificial Intelligence, page 464-467. Berlin, Heidelberg, Springer-Verlag, (July 2007)
M. Palmér, and A. Naeve. Proceedings of the 13th International Conference on Conceptual Structures (ICCS 2005), volume 3596 of Lecture Notes in Computer Science, page 136-151. Springer, (2005)
R. Dieng-Kuntz, and O. Corby. Proceedings of the 13th International Conference on Conceptual Structures (ICCS 2005), volume 3596 of Lecture Notes in Computer Science, page 19-50. Springer, (2005)