M. S., R., U. R., and S. Ramineni. “A Cross-Sectional Study on the Cardiac Imaging Methods Including Electrocardiograms and Echocardiography of the Heart in Patients With COPD”. International Journal of Research in Medical Sciences, vol. 13, no. 10, Sept. 2025, pp. 4054-9, doi:10.18203/2320-6012.ijrms20253141.