R. F. Guareschi, R. B. Brasil, A. Perin, and J. M. M. Ribeiro, “MAIZE AND SORGHUM HYBRIDS SILAGE PRODUCTION WITHOUT NITROGEN FERTILIZATION IN THE SUMMER GROWING SEASON”, Pesq. Agropec. Trop., vol. 40, no. 4, pp. 541–546, Dec. 2010, doi: 10.5216/pat.v40i4.6389.