^Madge, Steve; Burn, Hilary. Wildfowl : an identification guide to the ducks, geese and swans of the world. London: Christopher Helm. 1987. ISBN 0-7470-2201-1.
^Jobling, James A. The Helm Dictionary of Scientific Bird Names. London: Christopher Helm. 2010: 37. ISBN 978-1-4081-2501-4.