@misc{Birkenmajer_Aleksander_(1890-1967)_Z,
 author={Birkenmajer, Aleksander (1890-1967)},
 copyright={Birkenmajer-Hogard, Maria},
 address={Warszawa},
 howpublished={online},
 publisher={PWN},
 language={pol},
 title={Z dziejów autografu " De revolutionibus"},
 type={artykuł},
}