Anonymous. 1994. Proposal to transfer Aloe helenae and A. suzannae from Appendix II to Appendix I of CITES. Ninth Conference of the Parties to CITES, Fort Lauderdale, U.S.A.
Oldfield, S., Lusty, C. and MacKinven, A. (compilers). 1998. The World List of Threatened Trees. World Conservation Press, Cambridge, UK.
|Citation:||World Conservation Monitoring Centre 1998. Aloe helenae. The IUCN Red List of Threatened Species. Version 2014.2. <www.iucnredlist.org>. Downloaded on 31 July 2014.|