Smith, G. F., E. Figueiredo, F. Verloove, R. R. Klopper, and V. Silva. “An Annotated Catalogue of Aloe and Aloiampelos (Asphodelaceae Subfam. Alooideae) Naturalised and Escaped in Continental Portugal”. Phytotaxa, vol. 629, no. 1, Dec. 2023, pp. 35-52, doi:10.11646/phytotaxa.629.1.3.