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Harold A. Doty, Forrest B. Lee, Arnold D. Kruse, James W. Matthews, John R. Foster, Phillip M. Arnold, Wood Duck and Hooded Merganser Nesting on Arrowwood NWR, North Dakota, The Journal of Wildlife Management, Vol. 48, No. 2 (Apr., 1984), pp. 577-580
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Doty et al. (1984) studied this question.
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