PENG, R. A Method for Visualizing Multivariate Time Series Data. Journal of Statistical Software, Code Snippets, [S. l.], v. 25, n. 1, p. 1–17, 2008. DOI: 10.18637/jss.v025.c01. Disponível em: https://www.jstatsoft.org/index.php/jss/article/view/v025c01. Acesso em: 27 sep. 2022.