Choopan, T., P. J. Grote, K. Chayamarit, and D. A. Simpson. “Pollen Morphology of Subfamily Nelsonioideae (Acanthaceae) in Thailand”. Asia-Pacific Journal of Science and Technology, vol. 23, no. 2, Apr. 2018, pp. APST-23, doi:10.14456/kkurj.2018.7.