SK, M.; TB, S. The normal variations in heart rate and QRS complex of healthy individuals in different age groups. International Journal of Research in Medical Sciences, [S. l.], v. 2, n. 3, p. 861–865, 2017. Disponível em: https://www.msjonline.org/index.php/ijrms/article/view/2297. Acesso em: 2 jan. 2026.