Ruiloba, M., and C. Saldaña. “EVALUATION OF TWO LEVELS OF UREA ON A SALT-MINERAL MIXTURE AD LIBITUM OF PROTEIN FOR STEERS.”. Ciencia Agropecuaria, no. 12, Sept. 2002, pp. 177-89, http://200.46.165.126/index.php/ciencia-agropecuaria/article/view/346.