A. Hotho, R. Jäschke, C. Schmitz, and G. Stumme. The Semantic Web: Research and Applications, volume 4011 of Lecture Notes in Computer Science, page 411--426. Berlin/Heidelberg, Springer, (June 2006)
A. Hotho, R. Jäschke, C. Schmitz, and G. Stumme. Proceedings of the Conceptual Structures Tool Interoperability Workshop at the 14th International Conference on Conceptual Structures, Aalborg, Denmark, Aalborg University Press, (July 2006)