ZHANG, X. Analysis on Price Volatility between WTI Light Crude and Raw Coal. Journal of Mines, Metals and Fuels, [S. l.], v. 66, n. 9, p. 669–673, 2022. Disponível em: http://informaticsjournals.com/index.php/jmmf/article/view/31781. Acesso em: 9 may. 2024.