Smith, G.F. & Crouch, N.R. (2025) A review of the nomenclature and identity of Cotyledon mucronata and C. undulata (Crassulaceae subfam. Cotyledonoideae), two names variously applied to undulate leaf-margined material generally included in the synonymy of different varieties of C. orbiculata, with C. mucronata reinstated at the rank of species. Phytotaxa 714 (1): 40–56. https://doi.org/10.11646/phytotaxa.714.1.2