@incollection{Simmons91,
  author	= {Simmons, G.},
  editor	= {Klose, Gudrun and Lang, Ewald and Pirlein, Thomas},
  year		= {1991},
  title		= {Empirical methods for ontological engineering},
  booktitle	= {Die Ontologie und Axiomatik der Wissensbasis von LEU/2: Erfahrungen -- Probleme -- Ausblicke},
  number	= {IWBS Report 171},
  pages		= {VI. 1--38},
  institution	= {IBM Deutschland, Stuttgart}
}