@misc{Oncken_Wilhelm_(1838-1905)_Das,
 author={Oncken, Wilhelm (1838-1905)},
 address={Berlin},
 howpublished={online},
 publisher={G. Grote},
 language={ger},
 type={książka},
 title={Das Zeitalter Friedrich's des Grossen. Bd. 2},
 keywords={Fryderyk II Wielki (król Prus ; 1712-1786), Prusy -- 18 w},
}