J. Omer,S. , , M. Sulaiman,S. , , G. Karim,L. , and O. Ismail,A. . "Effect of different nitrogen levels on growth, yield and quality of two broccoli cultivars (Brassica oleraceae var. italica)", Kirkuk University Journal for Agricultural Sciences (KUJAS), 5, 2, 2014, 36-44. doi: 10.58928/ku14.05208