↑Germishuizen, G. & Meyer, N.L. (eds.) (2003). Plants of Southern Africa: an annotated checklist. Strelitzia 14.: i-vi, 1-1231. National Botanical Institute, Pretoria.
↑Onana, J.M. (2011). The vascular plants of Cameroon a taxonomic checklist with IUCN assessments: 1-195. National herbarium of Cameroon, Yaoundé.