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Ecology and Management of Breeding Waterfowl
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Bellrose, Frank C. 1976.
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The Birds of Africa. Volume I.
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The Howard & Moore Complete Checklist of the Birds of the World. Third Edition.
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Vida Animal: el Brehm ilustrado: Tomo Segundo
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Ducks, Geese, and Swans of the World
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Why do goose parents adopt unrelated goslings? A review of hypotheses and emperical evidence and new research questions
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A Phylogenetic Analysis of Recent Anseriform Genera Using Morphological Characters
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Houghton Mifflin Company. Boston, Massachusetts. 298 pgs.
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Salvadori, T. 1895.
Catalogue of the CHENOMORPHÆ (Palamedeæ, phoenicopteri, anseres), CRYPTURI, and RATITÆ in the collection of the British Museum
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The Birds of Israel
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Tibet and its birds
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