Berg, Å. (1991). Ecology of curlews (Numenius arquata) and lapwings (Vanellus vanellus) on farmland. Swedish University of Agricultural Sciences, Dept. of Wildlife Ecology.
Chicago-viite (17. p.)Berg, Åke. Ecology of Curlews (Numenius Arquata) and Lapwings (Vanellus Vanellus) on Farmland. Uppsala, Sweden: Swedish University of Agricultural Sciences, Dept. of Wildlife Ecology, 1991.
MLA-viite (8. p.)Berg, Åke. Ecology of Curlews (Numenius Arquata) and Lapwings (Vanellus Vanellus) on Farmland. Swedish University of Agricultural Sciences, Dept. of Wildlife Ecology, 1991.
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