O‘Hallorans, Julia M., Miguel A. Muñoz, and Octavio Colberg. “Effect of Chicken Manure on Chemical Properties of a Mollisol and Tomato Production”. The Journal of Agriculture of the University of Puerto Rico 77, no. 3-4 (October 1, 1993): 181–191. Accessed November 30, 2022. https://revistas.upr.edu/index.php/jaupr/article/view/4206.