Ali, Md Ansar, Md Shahidul Islam, Samir C Majumdar, Md Azizul Haque, and Amzad Hossain Sardar. “Role of Spirometry in Early Diagnosis of COPD Among Smokers”. TAJ: Journal of Teachers Association 32, no. 1 (August 22, 2019): 33–38. Accessed April 26, 2024. https://www.banglajol.info/index.php/TAJ/article/view/42733.