PERRINS, C M; OGILVIE, M A. A study of the Abbotsbury Mute Swans. Wildfowl, [S. l.], v. 32, p. 35–47, 1981. Disponível em: https://tidsskrift.dk/Wildfowl/article/view/154192. Acesso em: 4 apr. 2026.