Nassr عم, Assakkaf عع. The effect of nitrogen and phosphorus fertilization on some vegetative growth of three sunflower (Heliathus annus L.) cultivars. Univ. Aden J. Nat. and Appl. Sc. [Internet]. 2015 Apr. 30 [cited 2024 Dec. 3];19(1):13-2. Available from: https://uajnas.adenuniv.com/index.php/uajnas/article/view/269