@book{OPUS4-33360,
  title     = {Wprowadzenie do historii sredniowiecznej},
  editor    = {Heimann, Heinz-Dieter},
  publisher = {TNOIK},
  address   = {Turun},
  isbn      = {83-876773-73-0},
  pages     = {368 S.},
  year      = {1999},
  language  = {pl}
}
@book{Rheinberg2006,
  author    = {Rheinberg, Falko},
  title     = {Psychologia motywacji},
  publisher = {Wydawnictwo WAM},
  address   = {Krak{\´o}w},
  isbn      = {83-7318-640-9},
  pages     = {244 S.},
  year      = {2006},
  abstract  = {Polnische Ausgabe von "Motivation" 1. Aufl. 1995, 5. Aufl. 200},
  language  = {pl}
}