Crusciol, Carlos Alexandre Costa, et al. “Nutrition and Yield Behavior of Sorghum Hybrids With Contrasting Cycles Intercropped With Marandu Grass”. Pesquisa Agropecuaria Brasileira, vol. 46, no. 10, Jan. 2012, pp. 1234-40, doi:10.1590/S1678-3921.pab2011.v46.8529.