Naseer, Mehwish, et al. “FREQUENCY OF ABNORMAL PULMONARY FUNCTION TEST IN ASYMPTOMATIC SMOKERS UNDERGOING CORONARY ARTERY BYPASS GRAFTING”. Pakistan Armed Forces Medical Journal, vol. 72, no. SUPPL-1, Mar. 2022, pp. S72-75, https://pafmj.org/PAFMJ/article/view/8296.