Gastambide, Socorro, and Héctor R. Cibes. “Nutritional Deficiencies of Yams (Dioscorea spp.) and Related Effects on Yield and Leaf Composition”. The Journal of Agriculture of the University of Puerto Rico 59, no. 4 (October 1, 1975): 264–273. Accessed December 22, 2024. https://revistas.upr.edu/index.php/jaupr/article/view/10599.