Usberti-Filho, José Alfredo, et al. “Differential Vegetative and Reproductive Performances Among Fifteen Guinea Grass Hybrids”. Pesquisa Agropecuaria Brasileira, vol. 37, no. 2, Feb. 2002, pp. 139-43, doi:10.1590/S1678-3921.pab2002.v37.6320.