Rodríguez, A. A., R. B. Fuentes, and H. L. Díaz. “ANAEROBIC DIGESTION AND DIRECT ACIDIFICATION OF POULTRY PROCESSING SLUDGE FOR ANIMAL DIETS”. The Journal of Agriculture of the University of Puerto Rico, vol. 87, no. 1-2, Apr. 2003, pp. 81-86, doi:10.46429/jaupr.v87i1-2.1135.