@misc{DIN2331,
  author = {für Normung, Deutsches Institut},
  interhash = {f79d9b2723b5f23a90903b0752ae9a71},
  intrahash = {c91f8ddc2550f31dc7f163cd053808b8},
  title = {Begriffssysteme und ihre Darstellung},
  year = 1980
}