Pérez, J., G. Aldana, and C. Cárdenas. “Upflow Anaerobic Sludge Blanket Reactor (UASB) Performance through Sludge Age Load and Kinetic Coefficients”. Rev. Téc. Fac. Ing. Univ. Zulia, Vol. 35, no. 1, 1, https://produccioncientifica.luz.edu.ve/index.php/tecnica/article/view/6823.