OBADI, S. M.; KORECEK, M. The Crude Oil Price and Speculations: Investigation Using Granger Causality Test. International Journal of Energy Economics and Policy, [S. l.], v. 8, n. 3, p. 275–282, 2018. Disponível em: https://econjournals.com/index.php/ijeep/article/view/6333. Acesso em: 29 mar. 2024.