P. Øhrstrøm, und H. Schärfe. Proceedings of the 12th International Conference on Conceptual Structures (ICCS 2004), Volume 3127 von Lecture Notes in Computer Science, Seite 388-401. Springer, (2004)
D. Jakobsen, P. Øhrstrøm, und H. Schärfe. Proceedings of the 19th International Conference on Conceptual Structures (ICCS 2011), Volume 6828 von Lecture Notes in Computer Science, Seite 118-130. Springer, (2011)