Shah, Syed Alam, et al. “STUDY OF CORONARY ARTERY DISEASE IN PATIENTS OF YOUNGER AGE GROUP LESS THAN 40 YEARS OF AGE: Coronary Artery Disease”. Pakistan Armed Forces Medical Journal, vol. 68, no. 3, Oct. 2018, pp. 617-22, https://pafmj.org/PAFMJ/article/view/414.