PDF fulltext*Ian Sinclair, Phil Hockey and Warwick Tarboton, "SASOL Birds of Southern Africa" (Struik 2002) ISBN 1-86872-721-1*Madge and Burn, "Wildfowl" ISBN 0-7470-2201-1==External links==* Species text in The Atlas of Southern African Birds.
PDF fulltext* Ian Sinclair, Phil Hockey and Warwick Tarboton, "SASOL Birds of Southern Africa" (Struik 2002) ISBN 1-86872-721-1* Madge and Burn, "Wildfowl" ISBN 0-7470-2201-1