Beekman JH, Dirksen S, Slagboom TH. Population size and breeding success of Bewick’s Swans wintering in Europe in 1983-4. Wildfowl [Internet]. 1985 Nov. 1 [cited 2026 Apr. 19];36:5-12. Available from: https://tidsskrift.dk/Wildfowl/article/view/155040