MILLAR, R. S. Answer to ECG Quiz no. 33. SA Heart Journal, [S. l.], v. 11, n. 1, p. 36–37, 2017. DOI: 10.24170/11-1-1772. Disponível em: https://www.journals.ac.za/SAHJ/article/view/1772. Acesso em: 8 oct. 2025.