1. Collar, N. J. & Stuart, S. N. Key Forests for Threatened Birds in Africa (International Council for Bird Preservation Monograph No. 3) (Cambridge Univ. Press, 1988).
2. Huntley, B. J. J. S. Afr. Wildl. Mgmt. Assoc. 5, 157–166 (1974).
3. Mills, M. S. L., Melo, M. & Vaz, A. Bird Conserv. Int. 23, 159–167 (2013).
4. White, F. Afr. J. Ecol. 19, 33–54 (1981).
5. Vaz da Silva, B. A. D. N. Evolutionary History of the Birds of the Angolan Highlands - The Missing Piece to Understand the Biogeography of the Afromontane Forests. MSc. thesis, Univ. do Porto (2015).