MAYHEW, Peter W; HOUSTON, David C. Feeding behaviour of Wigeon Anas penelope on variable grassland swards. Wildfowl, [S. l.], v. 49, p. 181–185, 1998. Disponível em: https://tidsskrift.dk/Wildfowl/article/view/154619. Acesso em: 4 apr. 2026.