PERRINS, C M; SEARS, J. Collisions with overhead wires as a cause of mortality in Mute Swans Cygnus olor. Wildfowl, [S. l.], p. 5–11, 1991. Disponível em: https://tidsskrift.dk/Wildfowl/article/view/154084. Acesso em: 16 dec. 2025.