@misc{Heyke_Leon_(1885-1939)_[List,
 author={Heyke, Leon (1885-1939)},
 howpublished={online},
 language={csb},
 type={dokument piśmienniczy},
 title={[List Leona Heyke do Feliksa Marszałkowskiego], 1938.01.09},
}