Arroyo-Aguilú, J. A., Rivera-Brenes, L. and Cabrera, J. I. (1970) “Effect of Four Crude-Protein Concentrate Mixes upon Milk Production in Puerto Rico”, The Journal of Agriculture of the University of Puerto Rico, 54(1), pp. 76–81. doi: 10.46429/jaupr.v54i1.11114.