Daza, S., E. Gutiérrez, A. Galindo, J. Pérez, R. Rojando, and E. Toncel. “Effect of High Sulfate on Thermophilic Anaerobic Digestion of Synthetic Waste”. Rev. Téc. Fac. Ing. Univ. Zulia, Vol. 24, no. 3, 1, https://www.produccioncientificaluz.org/index.php/tecnica/article/view/5753.