Michener, Charles D., Michael D. Breed, and William J. Bell. 1979. “Seasonal Cycles, Nests, and Social Behavior of Some Colombian Halictine Bees (Hymenoptera; Apoidea)”. Revista De Biología Tropical 27 (1):13–34. https://revistas.ucr.ac.cr/index.php/rbt/article/view/25687.