Ref GC022: Colourful Cacti and Other Succulents of the Deserts by Edgar & Brian Lamb (1974)

The present popularity of cacti and other succulents stems from both their suitability as house plants, and also the considerable fascination their wide variety of growth and exotic flowers holds for many people.
Ref GC035: Cacti - The gardener's handbook for the Identification of Cultivation of Cacti by Professor John Borg

The gardener's handbook for the Identification of Cultivation of Cacti.