@misc{Kupczyk_Michał_Ornitologiczna_1993,
 author={Kupczyk, Michał},
 editor={Polish Academy of Sciences. Committee for Nature Conservation},
 copyright={Creative Commons Attribution BY 3.0 PL license},
 address={Kraków},
 howpublished={online},
 year={1993},
 publisher={Institute of Nature Conservation of the Polish Academy of Sciences},
 language={pol},
 title={Ornitologiczna wartość i możliwości ochrony dolin rzecznych w Wielkopolsce},
 title={Ornithological value and conservation problems concerning the river valleys of Wielkopolska},
 type={Text},
 URL={http://www.rcin.org.pl/Content/117127/PDF/KR038_135106_r1993_OchrPiS-Kupczyk-189-202.pdf},
 keywords={river valleys},
}