Institute for Aloe Studies(27th April, 2005): The propagation and conservation of the genus. The study of the genus and the education of the general public about this genus.
Cactus Neo(27th April, 2005): Pictures of hybrids.
Living Rocks(27th April, 2005): Reference on the genus.
Institute for Aloe Studies (): The propagation and conservation of the genus. The study of the genus and the education of the general public about this genus.
Agave (): Botanical database of the American Agavaceae.