[Sajeva M., McGough H. N., Garrett L., Lüthy J., Tse-Laurence M., Rutherford C., Sajeva G., CITES and Cacti: A User’s Guide, Kew Publishing, Royal Botanic Gardens, Kew, 2012, s. 84]
An illustrated botanical guide and training material with descriptions of cactus groups found in trade. The Pelecyphora section compares the characteristic areoles and spines of P. aselliformis with the triangular tubercles of P. strobiliformis and presents their slow growth. The taxonomy and regulatory information reflect the situation in July 2012.