ROSENBLAD, Andreas. gret1 1.7.3. Journal of Statistical Software, [S. l.], v. 25, n. 1, p. 1–14, 2008. DOI: 10.18637/jss.v025.s01. Disponível em: https://www.jstatsoft.org/index.php/jss/article/view/v025s01. Acesso em: 15 apr. 2025.