20210206215200.0 2664-8512 2664-8504 2664-8512 2664-8512 International journal of pulmonary and respiratory sciences (Dhaka. Online) International journal of pulmonary and respiratory sciences. Bangladesh International journal of pulmonary and respiratory sciences (Dhaka. Online) International journal of pulmonary and respiratory sciences. http://www.pulmonologyjournals.com 2664-8512