Figueiredo, E., and G. F. Smith. “John Forbes (1799–1823) in the Eastern Cape, South Africa, in 1822 and 1823: His Plant Collections and Collecting Localities”. Phytotaxa, vol. 659, no. 2, July 2024, pp. 165-9, doi:10.11646/phytotaxa.659.2.3.