Lin, C.-W., Phan, L.C.S. & Nguyen, N.H. (2021)

Begonia rigidifolia ssp. sonhungii (sect. Petermannia, Begoniaceae), a new subspecies from limestone hills in Central Vietnam

. Phytotaxa 498 (2): 139–144. https://doi.org/10.11646/phytotaxa.498.2.7