SERIE, Jerome R; BARTONEK, James C. Population status and productivity of Tundra Swans Cygnus columbianus in North America. Wildfowl, [S. l.], p. 172–177, 2013. Disponível em: https://tidsskrift.dk/Wildfowl/article/view/154987. Acesso em: 17 dec. 2025.