Martínez, Gustavo A., José L. Guzmán, Miguel A. Vázquez, Luis E. Rivera, and Agenol González. “Chemical and Physical Properties of Two Tropical Soils Treated With Sewage Sludge Compost”. The Journal of Agriculture of the University of Puerto Rico 83, no. 3-4 (October 1, 1999): 103–121. Accessed December 22, 2024. https://revistas.upr.edu/index.php/jaupr/article/view/3882.