PEIRó, A. Changes in the Unconditional Variance and Autoregressive Conditional Heteroscedasticity. International Journal of Economics and Financial Issues, [S. l.], v. 6, n. 4, p. 1338–1343, 2016. Disponível em: https://econjournals.com/index.php/ijefi/article/view/2643. Acesso em: 29 mar. 2024.