Swanepoel, Wessel, and Abraham E. Van Wyk. “Petalidium karasbergense (Acanthaceae), a New Species from Namibia”. Phytotaxa 609, no. 1 (August 17, 2023): 1–9. Accessed December 6, 2025. https://phytotaxa.mapress.com/pt/article/view/phytotaxa.609.1.1.