Irizarry, Héber, and Edmundo Rivera. “Yield of Two Yam (Dioscorea Alata) Cultivars With Three Planting Dates and Two Planting Systems”. The Journal of Agriculture of the University of Puerto Rico 77, no. 3-4 (October 1, 1993): 161–166. Accessed March 28, 2024. https://revistas.upr.edu/index.php/jaupr/article/view/4204.