@Proceedings{delugach01conceptual,

  title  = {Conceptual Structures -- Broadening the Base. Proc. 9th International Conference on Conceptual Structures},

  year   = {2001},
  number = {},
  url    = {},

  const  = {\ text}
}
@Proceedings{gronau01methoden,

  title  = {Methoden und Techniken der Wissensverarbeitung. Workshop der 1. Tagung Professionelles Wissensmanagement
                  --  Erfahrungen und Visionen },

  year   = {2001},
  number = {},
  url    = {http://wm2001.aifb.uni-karlsruhe.de/ws/ws7.html},

  const  = {\ text}
}
@Inproceedings{hereth01reverse,
  author = {Hereth, J. and Stumme, G.},
  title  = {Reverse Pivoting in Conceptual Information Systems.},

  year   = {2001},
  number = {},
  url    = {http://www.kde.cs.uni-kassel.de/stumme/papers/2001/ICCS01.pdf},

  const  = {\ text}
}
@Proceedings{schnurr01professionnelles,

  title  = {Professionelles Wissensmanagement -- Erfahrungen und Visionen. Proc. WM '01},

  year   = {2001},
  number = {},
  url    = {http://wm2001.aifb.uni-karlsruhe.de/},

  const  = {\ text}
}
@Proceedings{stumme01ontologies,

  title  = {Ontologies },

  year   = {2001},
  number = {},
  url    = {http://ceur-ws.org/Vol-48},

  const  = {\ text}
}