Yagi, Mahmoud, widad M. O. Modawei, and Mohammed Almubarak A. A. 2014. “Effect of Nitrogen and Spacing in Growth, Yield and Quality of Celocia Cristata”. International Journal of Sciences: Basic and Applied Research (IJSBAR) 18 (1):132-42. https://gssrr.org/index.php/JournalOfBasicAndApplied/article/view/2704.