“Effect of Foliar Nutrition by Humic and Fulvic Acid and the Interaction Between Them on Productivity of Sun Flower (Helianthus Annuus L.)”. Academic Science Journal 2, no. 3 (July 1, 2024): 66–78. Accessed April 5, 2025. https://acadscij.uodiyala.edu.iq/index.php/Home/article/view/512.