محمد يحيى م. Estimating simultaneous equations system of the world prices of the grains for the period (1961-2002). IRAQI JOURNAL OF STATISTICAL SCIENCES, [S. l.], v. 8, n. 2, p. 205–222, 2008. DOI: 10.33899/iqjoss.2008.31394. Disponível em: https://edusj.uomosul.edu.iq/index.php/stats/article/view/29148. Acesso em: 10 sep. 2025.