SMITH, Cyndi; COOKE, Fred; GOUDIE, R Ian. Ageing Harlequin Duck Histrionicus histrionicus drakes using plumage characteristics. Wildfowl, [S. l.], p. 245–248, 1998. Disponível em: https://tidsskrift.dk/Wildfowl/article/view/154601. Acesso em: 16 dec. 2025.