@inproceedings{stumme97tool,
  address = {Berlin},
  author = {Stumme, Gerd},
  booktitle = {Conceptual Structures: Fulfilling  Peirce's Dream. Proc. ICCS'97},
  editor = {Lukose, D. and Delugach, H. and Keeler, M. and Searle, L. and Sowa, J. F.},
  interhash = {fce31f95ec4537a11fd78e5081d63fe6},
  intrahash = {81bd13dbc2767c77b18bc3bd919fcc29},
  page = {318-331},
  publisher = {Springer},
  series = {LNAI},
  title = {Concept Exploration - A Tool for Creating and Exploring Conceptual Hierarchies},
  url = {http://www.kde.cs.uni-kassel.de/stumme/papers/1997/P1905-ICCS97.pdf},
  volume = 1257,
  year = 1997
}

@book{stumme97conceptexploration,
  address = {Aachen},
  author = {Stumme, Gerd},
  interhash = {e0e14593ffaef8fd0cb2d1564580ad5c},
  intrahash = {8e9d6d29a5b0764bbf2e18cabe2b8f2e},
  publisher = {Shaker},
  title = {Concept Exploration -- Knowledge Acquisition in Knowledge Systems. },
  url = {http://www.shaker.de/Online-Gesamtkatalog/details.asp?ISBN=3-8265-2930-8},
  year = 1997
}