A. A. Nunes, P. J. Moffa, and M. Iwasaki, “Standardization of a new precordial chest leads system in the dog”, Braz. J. Vet. Res. Anim. Sci., vol. 27, no. 2, pp. 233–246, Dec. 1990, doi: 10.11606/issn.0000-0000.272233-246.