DAFFALLA, Ahmed E. et al.
 Effect of  nitrogen on seed yield and content and quality of oil of winter grown sunflower (Helianthus annuus L.).
<strong>Gezira Journal of Agricultural Science</strong>, [S.l.], v. 11, n. 1, jan. 2013.
ISSN 1728-9556. Available at: &lt;<a href="http://37.60.236.48/index.php/gjas/article/view/52" target="_new">http://37.60.236.48/index.php/gjas/article/view/52</a>&gt;. Date accessed: 03 june 2026.