@book{GrafGrossSponagel1988,
  author    = {Graf, G{\"u}nter and Groß, Heinz and Sponagel, Stefan},
  title     = {Verfahren zur Herstellung eines Dichtringes : Europ{\"a}ische Patentschrift EP0250642B1 ; Ver{\"o}ffentlichungstag der Patentschrift: 11.02.1988},
  publisher = {Europ{\"a}isches Patentamt},
  address   = {[M{\"u}nchen u.a.]},
  pages     = {5 S. : Ill.},
  year      = {1988},
  language  = {de}
}
@book{Sponagel1982,
  author    = {Sponagel, Stefan},
  title     = {{\"U}ber die Stabilit{\"a}t einer einfachen viskometrischen Bewegung},
  address   = {Darmstadt},
  pages     = {106 S. : graph. Darst., 21 cm},
  year      = {1982},
  language  = {de}
}
@book{Sponagel1987,
  author    = {Sponagel, Stefan},
  title     = {Gummi-Metall-Bauteile},
  address   = {Kaiserslautern},
  pages     = {126 S. : Ill., graph. Darst.},
  year      = {1987},
  language  = {de}
}
@book{SponagelWachowitz1993,
  author    = {Sponagel, Stefan and Wachowitz, Waldemar},
  title     = {Wellendichtung : Europ{\"a}ische Patentschrift DE3621242C1 ; Ver{\"o}ffentlichungstag der Patentschrift : 06.06.1993 / Anmelder: Fa. Carl Freudenberg},
  publisher = {Europ{\"a}isches Patentamt},
  address   = {[M{\"u}nchen u.a.]},
  pages     = {5 S. : Ill.},
  year      = {1993},
  language  = {de}
}