HASAN, M. Z.; RATTI, R. A. Coal Sector Returns and Oil Prices: Developed and Emerging Countries. International Journal of Energy Economics and Policy, [S. l.], v. 5, n. 2, p. 515–524, 2015. Disponível em: https://www.econjournals.com/index.php/ijeep/article/view/1142. Acesso em: 21 jul. 2024.