Valdés, Freddy, Edmundo Muñoz, Rolando Chamy, Gonzalo Ruiz-Filippi, Christian Vergara, and David Jeison. 2006. “Effect of Sulphate Concentration and Sulphide Desorption on the Combined Removal of Organic Matter and Sulphate from Wastewaters Using Expanded Granular Sludge Bed (EGSB) Reactors”. Electronic Journal of Biotechnology 9 (4). Valparaíso, Chile:0-0. https://preprints.pucv.cl/index.php/ejbiotechnology/article/view/v9n4-11.