Averyanov, L. V., K. S. Nguyen, and H. T. Nguyen. “Checklist of Mycoheterotrophic Species of the Genus Exacum (Gentianaceae) and New Species, E. zigomorpha, from Northern Vietnam”. Phytotaxa, vol. 183, no. 2, Oct. 2014, pp. 108–113, doi:10.11646/phytotaxa.183.2.3.