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↑ Caley, Kevin (2007), “Fossil Birds”, trong del Hoyo, Josep; Elliott, Andrew; Christie, David, Handbook of the Birds of the World. Quyển 12, Picathartes to Tits and Chickadees, Barcelona: Lynx Edicions, tr. 11–56, ISBN84-96553-42-6
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↑ Sinclair I., Ryan P., Arlott N., Hayman P., Harris A., 2003, Birds of Africa: South of the Sahara, Princeton và Oxford: Nhà in Đại học Princeton, ISBN 978-0-691-11815-4. Ấn bản lần 2 (2010), ISBN 978-1-77007-623-5
↑ Curry-Lindahl K., 1981, Bird Migration in Africa: Movements between six continents, Quyển 2, New York: Academic Press, ISBN 978-0-12-200102-4
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↑ Hockey P. A. R., Dean W. R. J., Ryan P. G. (chủ biên), 2005, Roberts - Birds of Southern Africa, Ấn bản lần 7. Cape Town: The Trustees of the John Voelcker Bird Book Fund. Tr. 543. ISBN 0-620-34053-3
