@article{Ferrein2004,
  author    = {Ferrein, Alexander},
  title     = {Planwirtschaft},
  series = {Linux Magazin (2004)},
  journal   = {Linux Magazin (2004)},
  isbn      = {1432-640X},
  pages     = {50 -- 53},
  year      = {2004},
  language  = {de}
}
@incollection{BouvyKuperjans2004,
  author    = {Bouvy, C. and Kuperjans, Isabel},
  title     = {Mikro-Gasturbinen : eine neue Technologie zur Kraft-W{\"a}rme-Kopplung in kleinen und mittleren Unternehmen},
  series = {Entwicklungslinien der Energietechnik 2004},
  booktitle = {Entwicklungslinien der Energietechnik 2004},
  edition   = {CD-ROM-Ausg.},
  publisher = {VDI-Verlag},
  address   = {D{\"u}sseldorf},
  year      = {2004},
  language  = {de}
}