VINOGRADOV, V G; AUEZOV, E M. Numbers, distribution and breeding success of Whooper Swans Cygnus cygnus and Mute Swans C. olor in central Kazakhstan, USSR, in 1985 and 1987. Wildfowl, [S. l.], p. 73–76, 2013. Disponível em: https://tidsskrift.dk/Wildfowl/article/view/154998. Acesso em: 16 dec. 2025.