Lugo López, M.A. and Pérez Escolar, R. 1969. A Mathematical Approach to Evaluating the Influence of Various Factors on the Stability of Aggregates in Vertisols. The Journal of Agriculture of the University of Puerto Rico. 53, 1 (Jan. 1969), 57–60. DOI:https://doi.org/10.46429/jaupr.v53i1.11177.