@book{GerhardtKramerJansen1977,
  author    = {Gerhardt, Hans Joachim and Kramer, Carl and Jansen, Hubert},
  title     = {Traglufthallen unter Windbelastung},
  publisher = {Westdt. Verl.},
  address   = {Opladen},
  isbn      = {3-531-02650-X},
  pages     = {39 S. : Ill., graph. Darst.},
  year      = {1977},
  language  = {de}
}
@book{Gerhardt1977,
  author    = {Gerhardt, Hans Joachim},
  title     = {Untersuchungen zur aerodynamischen Detailoptimierung von Personenkraftwagen mit Hilfe von Modellversuchen im Windkanal / Carl Kramer ; Hans-Joachim Gerhardt; Siegfried Scherer},
  publisher = {Westdt. Verl.},
  address   = {Opladen},
  isbn      = {3-531-02633-X},
  pages     = {39 S. : Ill., graph. Darst.},
  year      = {1977},
  language  = {de}
}