Sikandar Ali Khan, Hina Hakim, Farzana Salman, Shamaila Wadud, Sara Yar Khan, and Momina Haq. 2026. “Effects of Vitamin D on Respiratory Function and Immune Status for Patients With Chronic Obstructive Pulmonary Disease (COPD): A Systematic Review”. Journal of Gandhara Medical and Dental Science 13 (3):132-42. https://doi.org/10.37762/jgmds.13-3.890.