1. C. W. Lukhoba, M. S. J. Simmonds, and A. J. Paton, J. Ethnopharmacol., 103, 1 (2006).
2. A. Hutchings, A. H. Scott, G. Lewis, U. O. Zululand, A. B. Cunningham, and N. B. Institute, Zulu Medicinal Plants: An Inventory, University of Natal Press, 1996.
3. P. Rijo, M. Gaspar, M. F. Simoes, A. Duarte, M. D. C. Apreda-Rojas, F. H. Cano, and B. Rodriguez, J. Nat. Prod., 65, 1387 (2002).
4. E. J. Van Jaarsveld, The Southern African Plectranthus and the Art of Turning Shade to Glade, Fernwood Press, 2006.
5. Plants of the World Online, Plectranthus alpinus (Vatke) Ryding. Royal Botanic Gardens Kew, Richmond, Surrey, UK. Accessed on 18th April 2020: http://www.plantsoftheworldonline.org/taxon/urn:lsid:ipni.org:names:1008549-1.