Patel KA, Patel PH, Vaid MP, Dandge V. A Case Control Study of Vitamin D Levels in Chronic Obstructive Pulmonary Disease Patients and Healthy Volunteers in South Gujarat, India. Natl J Med Res [Internet]. 2022 Dec. 31 [cited 2024 Dec. 30];12(04):73-6. Available from: https://njmr.in/index.php/file/article/view/931