Caraballo, Elvin, Megh Raj Goyal, and Carmela Chao de Báez. “Effects of Water Application Rates and Planting Density on Growth Parameters of Drip Irrigated Onions”. The Journal of Agriculture of the University of Puerto Rico 70, no. 2 (April 1, 1986): 135–141. Accessed November 30, 2022. https://revistas.upr.edu/index.php/jaupr/article/view/7085.