Magrini, S. & Scoppola, A. (2015)

Further studies in Viola Sect. Melanium (Violaceae). Identity and typification of Viola nana and V. henriquesii, two neglected European Atlantic taxa

. Phytotaxa 230 (3): 259–266. https://doi.org/10.11646/phytotaxa.230.3.4