Ubaid Ullah Sami, Saeed Ur Rehman, Adnan Ghafoor, Zayed Naser, Saleh Ahmad, Hafeez Ud Din. Serum Vitamin D Level in Chronic Obstructive Pulmonary Disease and its Relation with Severity. Pakistan Journal of Medical & Health Sciences [Internet]. 2022 Nov. 28 [cited 2024 Dec. 22];16(09):941. Available from: https://pjmhsonline.com/index.php/pjmhs/article/view/3030