Owen, Myrfyn; Thomas, G. J. (1979-01-01). "The Feeding Ecology and Conservation of Wigeon Wintering at the Ouse Washes, England". Journal of Applied Ecology. 16 (3): 795–809. doi:10.2307/2402854. JSTOR2402854.
jstor.org
Owen, Myrfyn; Thomas, G. J. (1979-01-01). "The Feeding Ecology and Conservation of Wigeon Wintering at the Ouse Washes, England". Journal of Applied Ecology. 16 (3): 795–809. doi:10.2307/2402854. JSTOR2402854.