References

For Operculina

Austin, D.F. 2023j. Operculina. In Flora of North America Editorial Committee. 2023c. Flora of North America north of Mexico. Volume 14, Magnoliophyta: Gentianaceae to Hydroleaceae. Oxford Univ. Press, New York, NY. 505 pp. Google Scholar

Staples, G.W., A.R. Simões, and D.F. Austin. 2020. A monograph of Operculina (Convolvulaceae). Ann. Missouri Bot. Gard. 105: 64-138. Google Scholar