Tovar-Puente, Aldo, Marisela Pando-Moreno, Humberto González-Rodríguez González-Rodríguez, Laura Scott-Morales, and Santiago de Jesús Méndez-Gallegos. “Density of Calcium Oxalate Crystals in 15 Prickly Pear Cultivated Species”. Journal of the Professional Association for Cactus Development 9 (October 6, 2007): 91–98. Accessed October 16, 2025. https://www.jpacd.org/jpacd/article/view/267.