ELTRINGHAM, S K; BOYD, H. The Shelduck population in the Bridgwater Bay moulting area. Wildfowl, [S. l.], v. 11, p. 107–117, 1960. Disponível em: https://tidsskrift.dk/Wildfowl/article/view/155704. Acesso em: 4 apr. 2026.