Mandal, N. C., S. Sabur, N. Ahsan, and K. Karmakar. “Evaluation of Pulmonary Function After Off- Pump Coronary Artery Bypass Graft Surgery With Thoracic Epidural Analgesia”. Cardiovascular Journal, vol. 6, no. 1, Aug. 2013, pp. 31-36, doi:10.3329/cardio.v6i1.16112.