@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{GerhardtKramer1982,
  author    = {Gerhardt, Hans Joachim and Kramer, Carl},
  title     = {Untersuchungen zur Lagesicherung von Flachd{\"a}chern mittels Kies- und Plattenabdeckungen},
  publisher = {IRB-Verl.},
  address   = {Stuttgart},
  pages     = {26, [18] S. : Ill., graph. Darst.},
  year      = {1982},
  language  = {de}
}
@book{GerhardtKramer1983,
  author    = {Gerhardt, Hans Joachim and Kramer, Carl},
  title     = {Windlasten auf nach innen geneigten Dachfl{\"a}chen},
  publisher = {IRB-Verl.},
  address   = {Stuttgart},
  pages     = {17, [11] Bl. : graph. Darst.},
  year      = {1983},
  language  = {de}
}