@misc{Lefébure_de_Fourcy_Louis_Etienne_(1785–1869)_Trygonometrya_1836,
 author={Lefébure de Fourcy, Louis Etienne (1785–1869)},
 editor={Kasterski, Franciszek (1805– ). Ed.},
 copyright={Public Domain},
 address={Warszawa},
 address={(Warszawa)},
 howpublished={online},
 year={1836},
 publisher={[s.n.]},
 publisher={(Drukarnia XX. Pijarów)},
 language={pol},
 type={Text},
 title={Trygonometrya},
 URL={http://www.rcin.org.pl/Content/34030/PDF/WA35_5753_6714_Trygonometrya.pdf},
}