@article{PietschKurbel1990,
  author    = {Pietsch, Wolfram and Kurbel, Karl},
  title     = {A Cooperative Work Environment for Evolutionary Software Development / Kurbel, K., Pietsch, W.},
  series = {Multi-user interfaces and applications : proceedings of the IFIP WG 8.4 Conference on Multi-User Interfaces and Applications, Heraklion, Crete, Greece, 24 - 26 September, 1990 / ed. by Simon Gibbs ...},
  journal   = {Multi-user interfaces and applications : proceedings of the IFIP WG 8.4 Conference on Multi-User Interfaces and Applications, Heraklion, Crete, Greece, 24 - 26 September, 1990 / ed. by Simon Gibbs ...},
  publisher = {North-Holland Publ.},
  address   = {Amsterdam [u.a.]},
  isbn      = {0-444-88760-1},
  pages     = {115 -- 127},
  year      = {1990},
  language  = {en}
}
@article{PietschSiedentopf1990,
  author    = {Pietsch, Wolfram and Siedentopf, J.},
  title     = {Wissensbasierte Programmierung in konventionellen Programmiersprachen - Entwicklung einer flexiblen Schnittstelle zur Expertensystementwicklung in Ada / Pietsch, W., Siedentopf, J.},
  series = {Wissensbasierte Systeme in der Betriebswirtschaft : Grundlagen, Entwicklung, Anwendungen / Hrsg. Dieter Ehrenberg ...},
  journal   = {Wissensbasierte Systeme in der Betriebswirtschaft : Grundlagen, Entwicklung, Anwendungen / Hrsg. Dieter Ehrenberg ...},
  publisher = {Schmidt},
  address   = {Berlin},
  isbn      = {3-503-03144-8},
  pages     = {233 -- 250},
  year      = {1990},
  language  = {de}
}
@article{Weigand1990,
  author    = {Weigand, Christoph},
  title     = {Optimal Adjustment Policies},
  series = {Proceedings of the First Ume{\aa}-W{\"u}rzburg Conference in Statistics : Kronlund Conference Center and University of Ume{\aa}, September 10 - 14, 1990 / ed. by Kurt Br{\"a}nn{\"a}s},
  journal   = {Proceedings of the First Ume{\aa}-W{\"u}rzburg Conference in Statistics : Kronlund Conference Center and University of Ume{\aa}, September 10 - 14, 1990 / ed. by Kurt Br{\"a}nn{\"a}s},
  publisher = {Univ. of Ume{\aa}},
  address   = {Ume{\aa}},
  isbn      = {91-7174-564-5},
  pages     = {147 -- 158},
  year      = {1990},
  language  = {en}
}