International Code of Botanical Nomenclature. Adopted by the Fourteenth International Botanical Congress, Berlin, July-August 1987.
Oberreifenberg: Koeltz, 1988. Octavo, More
Oberreifenberg: Koeltz, 1988. Octavo, More
Oxford: Clarendon Press, (1973. third edition), Octavo, text illustrations, very good copy in dustwrapper. More
Sydney: The Aloe, Cactus and Succulent Society of Rhodesia, 1971. Octavo, photographs. Full morocco grained cloth and marbled endpapers, the collector's edition numbered 50 to 150. This is copy 105. Issue number one of Excelsa, the journal of the Aloe, Cactus and Succulent Society of Rhodesia. More
Sydney: Australian Systematic Botany Society, 1990. Quarto, photographs, maps, signature, laminated boards. More
Edinburgh: Edinburgh University Press, 1989. Octavo, black and white photographs, text illustrations, as new in dustwrapper. More