Dr. Rakesh Kumar Shahi, Dr. Rajendra Rai, and Dr. P Nigam, “Electrocardiographic Findings and Its Comparison With Chronic Obstructive Pulmonary Disease Severity In Patients: A Prospective Study: Electrocardiographic Findings And Its Comparison With COPD Severity In Patients”, Natl J Integr Res Med, vol. 11, no. 4, pp. 15–18, Sep. 2020.