Mahammad Rafi, V. , Andrew R, S. and Ashok Vardhan, N. 2025. Association of Vitamin D Levels in Chronic Obstructive Pulmonary Disease. Journal of Neonatal Surgery. 14, 19S (Apr. 2025), 218–221. DOI:https://doi.org/10.63682/jns.v14i19S.4741.