JOURNAL, B. S. Effect of Nitrogen Fertilizer and Plant Density on Yield and Growth of Sunflower: Hasan A. Abbas | Hussain U. Khudair | AbudAsttar J. Hussain. مجلة بغداد للعلوم, Iraq, Baghdad, v. 5, n. 2, p. 188-192, 2008. DOI: 10.21123/bsj.2008.5.2.188-192. Disponível em: https://bsj.uobaghdad.edu.iq/index.php/BSJ/article/view/885. Acesso em: 18 2021.