1. Aschoff, J., &H. Pohl (1970): Rhythmic variations in energy metabolism. Proc. Fed. Am. Soc. Exp. Biol. 29: 1541–1552.
2. Boudewijn, T. (1984): The role of digestibility in the section of feeding sites by Brent Geese. Wildfowl 35: 97–105.
3. Fox, A. D., &J. Madsen (1981): The pre-nesting behaviour of the Greenland White-fronted Goose (Anser albifrons flavirostris). Wildfowl 32: 48–52.
4. Fox, A. D., A. Green, B. Hughes &G. Hilton (1994): Rafting as an antipredator response of wintering White-headed DuckOxyura leucocephala. Wildfowl 45: 232–241.
5. Frantzen, B. (1994): Steller's EiderPolysticta stelleri. In:Tucker, G. M. &M. F. Heath, Birds in Europe: their conservation status: 134–135. Cambridge.’