Attributes / relations provided by
♦ ¹del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona.
♦ ²Seed Dispersal by Birds in a South African and a Malagasy Commiphora Species, Bärbel Bleher, Katrin Böhning-Gaese, Ecotropica 6: 43–53, 2000