J. Bansode, R. Visaria, A. Varhadi, and D. Patania. International Journal on Recent and Innovation Trends in Computing and Communication, 3 (2):
852--855(February 2015)
V. Sklenár, M. Radvanský, and M. Dobes. Proceedings of the 15th International Conference on Conceptual Structures (ICCS 2007), volume 4604 of Lecture Notes in Artificial Intelligence, page 501-504. Berlin, Heidelberg, Springer-Verlag, (July 2007)