Jauregui, M. A., M. M. Gutiérrez, and H. O. Gutierrez. “Positive Solutions for a Coupled System of Non Linear of Second-Order Boundary-Valued Differential Equations”. GPH-International Journal of Mathematics, Vol. 8, no. 7, Aug. 2025, pp. 157-75, doi:10.5281/zenodo.16927158.