Goyder, D. 2008. Flora Malesiana, Series I. Volume 18. Apocynaceae (subfamilies Rauvolfioideae and Apocynoideae). D. J. Middleton. . Edinburgh Journal of Botany. 65, 1 (Feb. 2008), 157–158. DOI:https://doi.org/10.1017/S0960428608065116.