ديب ع. , صهيوني ف. and جعفر ر. 2021. Studying the Effect of Growth Regulator Naphthalene Acetic Acid (NAA) and Boron Element on Fruitset and Production of (Washington Navel) Citrus sinensis L. Osbeck. Tishreen University Journal -Biological Sciences Series. 43, 1 (Mar. 2021).