Götmark, F., M. Andersson, and O. Hildén. “Polymorphism in the Arctic Skua Stercorarius Parasiticus in NE Norway”. Ornis Fennica 58, no. 2 (July 1, 1981): 49–55. Accessed May 17, 2024. https://ornisfennica.journal.fi/article/view/133061.