López-Cervantes, R. “Humic Substances from Different Sources on Sorne Physical Properties of a Silty Clay Loamy Soil”. REVISTA TERRA LATINOAMERICANA 24, no. 3 (September 1, 2006): 303. Accessed December 24, 2024. https://terralatinoamericana.org.mx/index.php/terra/article/view/1483.