References
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Drilling, N., R. Titman, and F. McKinney. 2002. Mallard (Anas platyrhynchos). In The Birds of North America, No. 658 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia, PA.
Hepp, G. R., and F. C. Bellrose. 1995. Wood Duck (Aix sponsa). In The Birds of North America, No. 169 (A. Poole and F. Gill, eds.). The Academy of Natural Sciences, Philadelphia, and The American Ornithologists’ Union, Washington, D.C.
Hussell, D. J. T., and R. Montgomerie. 2002. Lapland Longspur (Calcarius lapponicus). In The Birds of North America, No. 656 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia, PA.
Johnson, K. 1995. Green-winged Teal (Anas crecca). In The Birds of North America, No. 193 (A. Poole and F. Gill, eds.). The Academy of Natural Sciences, Philadelphia, and The American Ornithologists’ Union, Washington, D.C.
Lyon, B., and R. Montgomerie. 1995. Snow Bunting and McKay’s Bunting (Plectrophenax nivalis and Plectrophenax hyperboreus). In The Birds of North America, No. 198–199 (A. Poole and F. Gill, eds.). The Academy of Natural Sciences, Philadelphia, and The American Ornithologists’ Union, Washington, D.C.
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Ringelman, J. K. 1990. Habitat Management for Molting Waterfowl. Colorado Division of Wildlife. Fish and Wildlife Leaflet 13.4.4.