R. Jäschke, A. Hotho, C. Schmitz, and G. Stumme. Proceedings of the 15th International Conference on Conceptual Structures, volume 4604 of LNCS, Sheffield, England, (July 2007)
F. Lehmann, and R. Wille. Conceptual structures: applications, implementation and theory, 954, page 32-43. Berlin--Heidelberg--New~York, Springer--Verlag, (1995)
G. Stumme. Proc. 3rd Intl. Conf. on Formal Concept Analysis, volume 3403 of Lecture Notes in Computer Science, page 315-328. Heidelberg, Springer, (2005)
P. Cimiano, A. Hotho, G. Stumme, and J. Tane. Proceedings of the The Second International Conference on Formal Concept Analysis (ICFCA 04), volume 2961 of LNCS, Springer, (2004)