U. Priss, N. Jensen, und O. Rod. Proceedings of the 21th International Conference on Conceptual Structures (ICCS 2013), Volume 7735 von Lecture Notes in Computer Science, Seite 121-134. Springer, (2013)
B. Galitsky, und S. Kuznetsov. Proceedings of the 16th International Conference on Conceptual Structures (ICCS 2008), Volume 5113 von Lecture Notes in Computer Science, Seite 282-296. Springer, (2008)