DE BOECK, P.; BAKKER, M.; ZWITSER, R.; NIVARD, M.; HOFMAN, A.; TUERLINCKX, F.; PARTCHEV, I. The Estimation of Item Response Models with the lmer Function from the lme4 Package in R. Journal of Statistical Software, [S. l.], v. 39, n. 12, p. 1–28, 2011. DOI: 10.18637/jss.v039.i12. Disponível em: https://www.jstatsoft.org/index.php/jss/article/view/v039i12. Acesso em: 30 jun. 2022.