C. Sacarea, R. Meza, and M. Cimpoi. Automation, Quality and Testing, Robotics, 2008. AQTR 2008. IEEE International Conference on, 3, page 234 -238. (May 2008)
R. Wille, and R. Wille-Henning. Conceptual structures: Knowledge architectures for smart applications. 15th international conference on conceptual structures, ICCS 2007, Sheffield, UK, July 22--27, 2007, volume 4604 of Lecture Notes in Computer Science, page 269--282. Berlin, Springer, (2007)Lecture Notes in Artificial Intelligence.
O. Bedel, S. Ferré, O. Ridoux, and E. Quesseveur. DEXA Work. Advances in Conceptual Knowledge Engineering (ACKE), page 540--544. Regensburg, Germany, IEEE Computer Society, (2007)
B. Ganter, and S. Kuznetsov. Conceptual Structures: Broadening the Base, volume 2120 of Lecture Notes in Computer Science, Springer Berlin Heidelberg, (2001)