CARSTENSEN, B.; PLUMMER, M. Using Lexis Objects for Multi-State Models in R. Journal of Statistical Software, [S. l.], v. 38, n. 6, p. 1–18, 2011. DOI: 10.18637/jss.v038.i06. Disponível em: https://www.jstatsoft.org/index.php/jss/article/view/v038i06. Acesso em: 2 dec. 2022.