Grupi, C. J., P. J. Moffa, S. A. Barbosa, P. C. Sanches, E. G. Barragan Filho, G. M. V. Bellotti, and F. J. C. Pileggi. “Holter Monitoring in Chagas’ Heart Disease”. São Paulo Medical Journal, vol. 113, no. 2, Mar. 1995, pp. 835-40, https://periodicosapm.emnuvens.com.br/spmj/article/view/1601.