J. Zhong, H. Zhu, J. Li, und Y. Yu. Proceedings of the 10th International Conference on Conceptual Structures (ICCS 2002), Volume 2393 von Lecture Notes in Computer Science, Seite 92-196. Springer, (2002)
K. Tu, J. Lu, H. Zhu, G. Liu, und Y. Yu. Proceedings of the 11th International Conference on Conceptual Structures (ICCS 2003), Volume 2746 von Lecture Notes in Computer Science, Seite 378-391. Springer, (2003)