1. Afton A, Paulus S (1992) Incubation and brood care. In: Batt BDJ, Afton BD, Anderson MG, Ankney CD, Johnson DH, Kadlec JA, Krapu GL (eds) Ecology and management of breeding waterfowl. University of Minnesota Press, Minneapolis, pp 62–108
2. Agresti A (2002) Categorical data analysis, 2nd edn. Wiley, Hoboken
3. Ahlén I, Andersson Å (1970) Breeding ecology of an eider population on Spitsbergen. Ornis Scand 1:83–106
4. Åhlund M (2005) Behavioural tactics at nest visits differ between parasites and hosts in a brood parasitic duck. Anim Behav 70:433–440
5. Alisauskas RT, Ankney CD (1992) The cost of egg laying and its relationship to nutrient reserves in waterfowl. In: Batt BDJ, Afton BD, Anderson MG, Ankney CD, Johnson DH, Kadlec JA, Krapu GL (eds) Ecology and management of breeding waterfowl. University of Minnesota Press, Minneapolis, pp 30–61