Smith, G. F., R. R. Klopper, N. R. Crouch, and E. Figueiredo. “Reinstatement of Aloe davyana Var. subolifera (Asphodelaceae Subfam. Alooideae), a Distinctive Variety of an Endemic South African Aloe”. Phytotaxa, vol. 482, no. 2, Jan. 2021, pp. 208–212, doi:10.11646/phytotaxa.482.2.9.