Amabile, Renato Fernando, et al. “Growth Analysis of Sunflower in a Cerrado Oxisol With Different Levels of Basis Saturation”. Pesquisa Agropecuaria Brasileira, vol. 38, no. 2, Feb. 2003, pp. 219-24, doi:10.1590/S1678-3921.pab2003.v38.6564.