Rivera-Zayas, Johanie, et al. “Nitrogen Fertilizer Rate for Improving Inbred Maize (Zea Mays L.) Yield on the Semi-Arid Southern Coast of Puerto Rico”. The Journal of Agriculture of the University of Puerto Rico, vol. 101, no. 2, Oct. 2017, pp. 185-02, doi:10.46429/jaupr.v101i2.15789.