Fernández, N., and C. Forster. “A Comparative Examination of the Start-up of a Mesophilic and a Thermophilic Anaerobic Filter Treating a Synthetic Coffee Waste”. Rev. Téc. Fac. Ing. Univ. Zulia, Vol. 17, no. 2, 1, http://www.produccioncientifica.luz.edu.ve/index.php/tecnica/article/view/5442.