BOYD, Hugh. Pink-footed Geese Anser brachyrhynchus on the Moorfoot Hills, Scotland, in spring 1952-1981. Wildfowl, [S. l.], p. 27–35, 1998. Disponível em: https://tidsskrift.dk/Wildfowl/article/view/154609. Acesso em: 16 dec. 2025.