Nilsson, Leif, and Fredrik Haas. “Distribution and Numbers of Wintering Waterbirds in Sweden in 2015 and Changes During the Last Fifty Years”. Ornis Svecica 26, no. 1 (January 1, 2016): 3–54. Accessed November 22, 2024. https://journals.lub.lu.se/os/article/view/21854.