Akhter, S., Mustafa, E., Salehin, M., Yeasmin, N., & Amin, M. R. (2015). Study of FVC,FEV1 & FEV1/FVC% in adult male smokers. Bangladesh Journal of Medicine, 26(2), 61–66. https://doi.org/10.3329/bjmed.v26i2.25450