Cervantes-Ortíz, F.; Covarrubias-Prieto, J.; Rangel-Lucio, J. A.; Terrón-Ibarra, A. D.; Mendoza-Elos, M.; Preciado-Ortiz, R. E. Population Density and Application of Nitrogen in the Production of Hybrid Corn Seed. Agron. Mesoam. 2013, 24, 101-110.