Mustafa, Nadia A., Omer E. Y. Elhag, Abdelrahman M. Abukanna, Ahmed H. Sulaiman, and Hafiz O. IbnIdris. “The Relationship Between Vitamin D Level and Severity and Control of Bronchial Asthma Among Adult Sudanese Patients”. International Journal of Research in Medical Sciences 6, no. 5 (April 25, 2018): 1649–1654. Accessed October 12, 2025. https://www.msjonline.org/index.php/ijrms/article/view/4784.