Averyanov, L.V., Nguyen, K.S. and Nguyen, H.T. 2014. Checklist of mycoheterotrophic species of the genus <em>Exacum</em> (Gentianaceae) and new species, <em>E. zigomorpha</em>, from northern Vietnam. Phytotaxa. 183, 2 (Oct. 2014), 108–113. DOI:https://doi.org/10.11646/phytotaxa.183.2.3.