KRIVONOSOV, G A. The status and distribution of the Mute Swan Cygnus olor in the USSR: a review of recent censuses. Wildfowl, [S. l.], p. 33–38, 2013. Disponível em: https://tidsskrift.dk/Wildfowl/article/view/155006. Acesso em: 17 dec. 2025.