Ramos Santana, Rafael, and José E. Rodríguez. “Twenty Genotypes of Panicum Maximum in the Humid Highlands of Puerto Rico”. The Journal of Agriculture of the University of Puerto Rico 78, no. 1-2 (April 1, 1994): 9–16. Accessed October 2, 2022. https://revistas.upr.edu/index.php/jaupr/article/view/4248.