Silva, Paulo Regis Ferreira da, and Eduardo Schmidt. 2014. “Effect of Density and Arrangement of Plants on Sunflower. I. Achene and Oil Yields, Oil Percent and Yield Components”. Pesquisa Agropecuaria Brasileira 21 (2):165-71. https://doi.org/10.1590/S1678-3921.pab1986.v21.14684.