Kahlert, Johnny, Aivar Leito, Bjarke Laubek, Leho Luigujõe, Andres Kuresoo, Kim Aaen, and Aarne Luud. “Factors Affecting the Flight Altitude of Migrating Waterbirds in Western Estonia”. Ornis Fennica 89, no. 4 (December 31, 2012): 241–253. Accessed November 21, 2024. https://ornisfennica.journal.fi/article/view/133812.