@misc{LauthMuellerHoelderich1994,
  author    = {Lauth, Jakob and M{\"u}ller, Ulrich and Hoelderich, Wolfgang},
  title     = {Preparation of aluminophosphates and silicoaluminophosphates having the AEL structure using 1,2-bis-( 4-pyridyl)-ethane : United States Patent ; patent number 5,324,493 ; date of patent: Jun. 28, 1994 / assignee: BASF Aktiengesellschaft. Inventors: Ulrich Mueller ; Wolfgang Hoelderich ; Guenter Lauth},
  publisher = {[United States Trademark and Patent Office]},
  address   = {[Alexandria, VA]},
  pages     = {6 S. : Ill.},
  year      = {1994},
  language  = {en}
}
@misc{SponagelWachowitz1992,
  author    = {Sponagel, Stefan and Wachowitz, Waldemar},
  title     = {Shaft seal : United States Patent 5,143,385 ; date of patent: Sep. 1, 1992 / assignee: Firma Carl Freudenberg},
  publisher = {[United States Patent and Trademark Office]},
  address   = {[Alexandria, VA]},
  pages     = {5 S. : Ill.},
  year      = {1992},
  language  = {en}
}
@misc{BerndtHoeckerKuropkaetal.1991,
  author    = {Berndt, Heinz and H{\"o}cker, Hartwig and Kuropka, Rolf and Kinkel, Joachim},
  title     = {Silane coated inorganic materials for chromatography : United States Patent},
  publisher = {[The United States Patent and Trademark Office]},
  address   = {[Alexandria, VA u.a.]},
  pages     = {9 S. : graph. Darst.},
  year      = {1991},
  language  = {en}
}
@misc{SponagelGrafGross1989,
  author    = {Sponagel, Stefan and Graf, G{\"u}nter and Groß, Heinz},
  title     = {Method for manufacturing a sealing ring : United States Patent 4,861,536 ; date of patent: Aug. 12, 1989 / assignee: Firma Carl Freudenberg. Inventors: Gunter Graf ; Heinz Gross ; Stefan Sponagel},
  publisher = {[United States Patent and Trademark Office]},
  address   = {[Alexandria, VA]},
  pages     = {5 S. : Ill.},
  year      = {1989},
  language  = {en}
}
@misc{SponagelGrafGross1989,
  author    = {Sponagel, Stefan and Graf, G{\"u}nter and Groß, Heinz},
  title     = {Method for the manufacture of a sealing ring with a sealing lip having hydrodynamically acting return elements : United States Patent 4,850,097 ; date of patent: Jul. 25, 1989 / assignee: Firma Carl Freudenberg. Inventors: Gunter Graf ; Heinz Gross ; Stefan Sponagel},
  publisher = {[United States Patent and Trademark Office]},
  address   = {[Alexandria, VA]},
  pages     = {4 S. : Ill.},
  year      = {1989},
  language  = {en}
}