1.
Nilsson L. Changes in numbers and habitat utilization of wintering Whooper Swans Cygnus cygnus in Sweden 1964—1977. Ornis Svec [Internet]. 1997 Oct. 1 [cited 2024 Oct. 6];7(3–4):133-42. Available from: https://journals.lub.lu.se/os/article/view/22966