Wessel-Beaver, Linda, César Cardona Castro, and Paul R. Hepperly. “Agronomic Performance of Hard Endosperm Opaque-2 Corn Populations in Puerto Rico”. The Journal of Agriculture of the University of Puerto Rico 72, no. 2 (April 1, 1988): 309–317. Accessed August 15, 2022. https://revistas.upr.edu/index.php/jaupr/article/view/7852.