Stumme, G.
(1997).
Concept Exploration - A Tool for Creating and Exploring Conceptual Hierarchies.
In D. Lukose, H. Delugach, M. Keeler, L. Searle & J. F. Sowa (eds.),
Conceptual Structures: Fulfilling Peirce's Dream. Proc. ICCS'97,
Berlin: Springer.