1. Hutchinson J., Dalziel J. M. The flora of West Tropical Africa. 2nd Edition. Crown Agents, London 1948; Vol. II: 65
2. Metcalfe C. R., Chalk L. Anatomy of the Dicotyledons. Clarendon Press, London 1965; Vol. II: 905–908
3. Alkaloids of Tabernaemontana divaricata