Volatility modelling of crude oil prices using a five-states Figarch-Hidden Markov model frame work. JOURNAL OF BASICS AND APPLIED SCIENCES RESEARCH, [S. l.], v. 4, n. 1, p. 97–112, 2026. DOI: 10.4314/jobasr.v4i1.11. Disponível em: https://jobasrfudutsinma.com/index.php/ojs-files/article/view/17. Acesso em: 6 mar. 2026.