G. F. Smith, “Infrageneric nothotaxa recognised in Kalanchoe (Crassulaceae [subfam. Cotyledonoideae] tr. Kalanchoeae): new names published at the ranks of nothosubgenus, nothosection, and nothoseries”, Phytotaxa, vol. 781, no. 2, pp. 137–150, Oct. 2026.