C. Pshenichny, and D. Mouromtsev. Proceedings of the 21th International Conference on Conceptual Structures (ICCS 2013), volume 7735 of Lecture Notes in Computer Science, page 289-300. Springer, (2013)
B. Krause, R. Jäschke, A. Hotho, and G. Stumme. HT '08: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia, page 157-166. New York, NY, USA, ACM, (2008)