Schanzer, Ivan A. “Systematic notes on Ophiorrhiza trichocarpon Blume (Rubiaceae) and some related species”. Thai Forest Bulletin (Botany), no. 32 (December 8, 2014): 132–145. accessed October 11, 2026. https://li01.tci-thaijo.org/index.php/ThaiForestBulletin/article/view/24368.