BEE DAGUM, E.; CAPITANIO, A. Smoothing methods for short-term trend analysis: cubic splines and Henderson filters. Statistica, [S. l.], v. 58, n. 1, p. 5–24, 1998. DOI: 10.6092/issn.1973-2201/1074. Disponível em: https://rivista-statistica.unibo.it/article/view/1074. Acesso em: 26 oct. 2021.