Felker, P., and R. Bunch. “The Importance of Native Bees, Especially Cactus Bees (Diadasia Spp) in the Pollination of Cactus Pears”. 2016. Journal of the Professional Association for Cactus Development, vol. 18, June 2020, pp. 15-24, doi:10.56890/jpacd.v18i.49.