KOFFIJBERG, Kees et al. Decline of the Bewick’s Swan Cygnus columbianus bewickii population wintering in Northeast/Northwest Europe. Wildfowl, [S. l.], v. 75, p. 63–93, 2025. Disponível em: https://tidsskrift.dk/Wildfowl/article/view/162735. Acesso em: 13 dec. 2025.