RAJASEKHAR, K. A prospective study of ECG and echocardiographic changes in chronic obstructive pulmonary disease patients in a tertiary care hospital. International Journal of Health and Clinical Research, [S. l.], v. 3, n. 12, p. 40–42, 2020. Disponível em: https://ijhcr.com/index.php/ijhcr/article/view/554. Acesso em: 14 dec. 2025.