Román-García, F., R. E. McDowell, H. Cestero, J. D. Rivera-Anaya, and J. A. Arroyo-Aguilú. 1979. “Performance of Holstein Cows Born in Puerto Rico Versus Cows Imported from the United States”. The Journal of Agriculture of the University of Puerto Rico 63 (1):13-21. https://doi.org/10.46429/jaupr.v63i1.10303.