@book{HentzeMuellerSchlicksupp1990,
  author    = {Hentze, Henner and M{\"u}ller, Klaus-Dieter and Schlicksupp, Helmut},
  title     = {Praxis der Managementtechniken},
  edition   = {1. Auf.},
  publisher = {Hanser},
  address   = {M{\"u}nchen [u.a.]},
  isbn      = {3-446-15046-3},
  pages     = {256 S. : graph. Darst.},
  year      = {1990},
  language  = {de}
}
@book{Hentze2005,
  author    = {Hentze, Henner},
  title     = {Alternde Belegschaften - Herausforderungen f{\"u}r die Unternehmen},
  address   = {IHK M{\"u}nster},
  year      = {2005},
  language  = {de}
}