Estimating the optimal model for the crude oil production chain of the Organization of Crude Oil Exporting Countries (OPEC) for the period (2005-2010). Journal of the College of Basic Education, [S. l.], v. 19, n. 80, p. 63–79, 2022. DOI: 10.35950/cbej.v19i80.7885. Disponível em: https://cbej.uomustansiriyah.edu.iq/index.php/cbej/article/view/7885.. Acesso em: 2 jul. 2024.