@book{PfeifferKnepper1995,
  author    = {Pfeiffer, Johann and Knepper, Ludger},
  title     = {Diplom-Ingenieur/Diplom-Ingenieurin ( Fachhochschule ) Maschinenbau - Allgemeiner Maschinenbau},
  publisher = {Bertelsmann},
  address   = {Bielefeld},
  pages     = {Losebl.-Ausg.},
  year      = {1995},
  language  = {de}
}
@book{Baatz1981,
  author    = {Baatz, Udo},
  title     = {Diplom-Ingenieur / Diplom-Ingenieurin an Fachhochschulen: Fachrichtung Maschinenbau : Stand: Dezember 1980},
  publisher = {Bertelsmann},
  address   = {Bielefeld},
  pages     = {31 S., Beil.},
  year      = {1981},
  language  = {de}
}
@book{KnepperPfeiffer1999,
  author    = {Knepper, Ludger and Pfeiffer, Johann},
  title     = {Diplom-Ingenieur / Diplom-Ingenieurin (Fachhochschule) Maschinenbau, Energie- und W{\"a}rmetechnik},
  publisher = {Bertelsmann},
  address   = {Bielefeld},
  pages     = {Loseblattausg.},
  year      = {1999},
  language  = {de}
}
@book{PfeifferKnepper1998,
  author    = {Pfeiffer, Johann and Knepper, Ludger},
  title     = {Diplom Ingenieur/Diplom Ingenieurin (Fachhochschule) Maschinenbau Konstruktionstechnik},
  publisher = {Bertelsmann},
  address   = {Bielefeld},
  pages     = {Losebl.-Ausg.},
  year      = {1998},
  language  = {de}
}
@book{Seehausen2008,
  author    = {Seehausen, Gerhard},
  title     = {Digitale Signalverarbeitung : Grundlagen / Gerhard H. F. Seehausen},
  publisher = {Mainz},
  address   = {Aachen},
  isbn      = {3-86130-604-2},
  pages     = {104 S. : graph. Darst.},
  year      = {2008},
  language  = {de}
}
@book{DavidBenkner1996,
  author    = {David, Klaus and Benkner, Thorsten},
  title     = {Digitale Mobilfunksysteme},
  publisher = {Teubner},
  address   = {Stuttgart},
  pages     = {XIII, 457 S graph. Darst., + 1 Kt.},
  year      = {1996},
  language  = {de}
}
@book{DavidBenkner2013,
  author    = {David, Klaus and Benkner, Thorsten},
  title     = {Digitale Mobilfunksysteme},
  number    = {Repr. 1996},
  publisher = {Vieweg \& Teubner},
  address   = {Wiesbaden},
  isbn      = {978-3-322-92768-2},
  pages     = {XIII, 458 S.},
  year      = {2013},
  language  = {de}
}
@book{JanzEblingGottschalketal.2000,
  author    = {Janz, Norbert and Ebling, G{\"u}nther and Gottschalk, Sandra and Niggemann, Hiltrud},
  title     = {Dienstleistungen in der Zukunft: Innovationsaktivit{\"a}ten im Dienstleistungssektor. Ergebnisse der Erhebung 1999 / Janz, N., G. Ebling, S. Gottschalk und H. Niggemann},
  publisher = {ZEW Zentrum f{\"u}r Europ{\"a}ische Wirtschaftsforschung},
  address   = {Mannheim},
  year      = {2000},
  language  = {de}
}
@book{JanzEblingHippetal.1998,
  author    = {Janz, Norbert and Ebling, G{\"u}nther and Hipp, C. and Licht, Georg},
  title     = {Dienstleistungen in der Zukunft : Innovationsaktivit{\"a}ten im Dienstleistungssektor ; Befragung 1997 ; Kurzfassung / Janz, N., G. Ebling, C. Hipp, G. Licht und H. Niggemann},
  publisher = {ZEW Zentrum f{\"u}r Europ{\"a}ische Wirtschaftsf{\"o}rderung},
  address   = {Mannheim},
  year      = {1998},
  language  = {de}
}
@book{JanzEblingGottschalketal.1999,
  author    = {Janz, Norbert and Ebling, G{\"u}nther and Gottschalk, Sandra and Licht, Georg},
  title     = {Dienstleistungen in der Zukunft: Innovationsaktivit{\"a}ten im Dienstleistungssektor. Befragung 1998 / Janz, N., G. Ebling, S. Gottschalk, G. Licht und H. Niggemann},
  publisher = {ZEW Zentrum f{\"u}r Europ{\"a}ische Wirtschaftsforschung},
  address   = {Mannheim},
  year      = {1999},
  language  = {de}
}