de Almeida, M. L., & da Silva, P. R. F. (1993). Effect of plant density, sowing date and fertilization on the sunflower agronomic characteristics. I. Grain yield and oil and yield components. Pesquisa Agropecuaria Brasileira, 28(7), 833–841. https://doi.org/10.1590/S1678-3921.pab1993.v28.3944