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Sarah E. Jamieson, Gregory J. Robertson, H. Grant Gilchrist, Autumn and Winter Diet of Long-Tailed Duck in the Belcher Islands, Nunavut, Canada, Waterbirds: The International Journal of Waterbird Biology, Vol. 24, No. 1 (Apr., 2001), pp. 129-132
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Jamieson et al. (2001) studied this question.
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