de Mendonça, M.M. et al. 2006. Genotypic variability of maize for nitrogen accumulation and contribution of biological nitrogen fixation. Pesquisa Agropecuaria Brasileira. 41, 11 (Nov. 2006), 1681–1685. DOI:https://doi.org/10.1590/S1678-3921.pab2006.v41.7332.