George Engelmann: Botanical Appendix. In: Friedrich Adolph Wislizenus: Memoir of a tour to northern Mexico: connected with Col. Doniphan’s expedition, in 1846 and 1847. 1848, S. 102 (online).
N. L. Britton, J. N. Rose: The Genus Cereus and its Allies in North America. In: Contributions from the United States National Herbarium. Band 12, S. 428, 1909 (online).
