R. Jäschke, A. Hotho, C. Schmitz, B. Ganter, and G. Stumme. Proceedings of the 6th IEEE International Conference on Data Mining (ICDM 06), page 907-911. Hong Kong, IEEE Computer Society, (December 2006)
G. Stumme. Conceptual Structures: Knowledge Representation as Interlingua Proc. ICCS'96, volume 1115 of LNAI, page 308-320. Heidelberg, Springer, (1996)
F. Lehmann, and R. Wille. Conceptual structures: applications, implementation and theory, 954, page 32-43. Berlin--Heidelberg--New~York, Springer--Verlag, (1995)
K. Becker, G. Stumme, R. Wille, U. Wille, and M. Zickwolff. Knowledge Engineering and Knowledge Management. Methods, Models, and Tools., volume 1937 of LNAI, page 352-365. Heidelberg, Springer, (2000)