Callejas, Edwin Alberto, Jonathan Alexis Escalante-Ramírez, Henry Adalberto Pinto-Cristino, Erik Manrrique Arita-Barahona, Adones Antonio Calles-Cuellar, and Fabio Ernesto Ramos-Reyes. “Proposal for Attendance and Retention Control at Universidad Tecnológica De El Salvador”. Entorno, no. 68 (December 30, 2019): 142–151. Accessed October 19, 2024. https://camjol.info/index.php/entorno/article/view/8444.