Bayer, Bruce, 1999,
Haworthia Revisited, A Revision of the
Genus: Umdaus Press, Hatfield, South
We have species that
Bayer (1999) no longer considers viable,
and we list these either among the
hybrids or in parentheses [e.g.,
Haworthia reticulata (ambigua)]. We also have begun to expand past the Bayer (1999) framework, incorporating some of Breuer's names as well with notation to that effect. We also rely on Gerhard Marx and Vincent de Vries for help with this complicated genus.
Schulz, R.S., 2009, Haworthia for the Collector: Schulz Publishing, San Bruno, CA
van Jaarsveld, E.J., 1992. Aloe, v. 29.
van Jaarsveld, E.J.,
1995, Gasterias of South Africa:
Fernwood Press, Vlaeberg, South Africa.
van Jaarsveld, E.J., 2007. Aloe, v. 44.