SEREBRYAKOV, V V; GRISHCHENKO, V N; POLUDA, A M. The migration of swans Cygnus spp., in the Ukraine, USSR. Wildfowl, [S. l.], p. 218–223, 2013. Disponível em: https://tidsskrift.dk/Wildfowl/article/view/154975. Acesso em: 17 dec. 2025.