VAN ZYL, R.; VAN DER MERWE, A. J. Phase I and Phase II control charts for the variance and generalized variance. South African Statistical Journal, [S. l.], v. 50, n. 1, p. 65–80, 2016. DOI: 10.37920/sasj.2016.50.1.3. Disponível em: https://www.journals.ac.za/index.php/sasj/article/view/5532. Acesso em: 3 apr. 2026.