Chelme, S., P. Fonseca, R. Mercado, N. A. Alarcón-Pulido, and O. Sánchez. “Macromolecular Composition and Anaerobic Degradation of the Sludge Produced in a Sequencing Batch Reactor”. Electronic Journal of Biotechnology, vol. 11, no. 3, June 2008, pp. 0-0, https://www.ejbiotechnology.info/index.php/ejbiotechnology/article/view/v11n3-12.