KONDRATIEV, A Ya. Breeding biology of Bewick’s Swans Cygnus bewickii in Chukotka, Far Eastern USSR. Wildfowl, [S. l.], p. 167–171, 2013. Disponível em: https://tidsskrift.dk/Wildfowl/article/view/154983. Acesso em: 17 dec. 2025.