BEEKMAN, Jan H; VAN EERDEN, Mennobart R; DIRKSEN, Sjoerd. Bewick’s Swan Cygnus columbianus bewickii utilising the changing resource of Potamogeton pectinatus during autumn in the Netherlands. Wildfowl, [S. l.], p. 238–248, 2013. Disponível em: https://tidsskrift.dk/Wildfowl/article/view/154977. Acesso em: 17 dec. 2025.