References
- Lawson , W. J. 1962 . Variation in the South African populations of the coucal Centropus superciliosus Hemprich and Ehrenberg. . Ostrich , 33 : 45 – 47 .
- Mackworth-Praed , C. W. and Grant , C. H. B. 1962 . Birds of the southern third of Africa Vol. 1 , London : Longmans .
- Snow , D. W. and Clancey , P. A. 1978 . “ Cuculidae. ” . In An Atlas of speciation in African non-passerine birds. Edited by: Snow; , D. W. London : British Museum (Natural History). .