Mangual-Crespo, Gerardo. “Yield of Two Sweet Corn Varieties and Two Hybrids in the Isabela Area”. The Journal of Agriculture of the University of Puerto Rico 61, no. 2 (April 1, 1977): 175–178. Accessed April 24, 2024. https://revistas.upr.edu/index.php/jaupr/article/view/10455.