We have information from several sources:
Native Cultivars of Cactus Pear in MéxicoC. Mondragon-Jacobo and S. Perez-Gonzalez
Mediterranean FruitsJoan Tous and Louise Ferguson
Commercializing Mesquite, Leucaena, and Cactus in TexasPeter Felker
Low Input Agricultural Systems Based on Cactus Pear for Subtropical Semiarid EnvironmentsCandelario Mondragon Jacobo
Magness, J.R., G.M. Markle, C.C. Compton. 1971. Food and feed crops of the United States.