FREEDMAN, R. S.; FRAIL, R. P. OPGEN: The Evolution of an Expert System for Process Planning. AI Magazine, [S. l.], v. 7, n. 5, p. 58, 1986. DOI: 10.1609/aimag.v7i5.566. Disponível em: https://ojs.aaai.org/aimagazine/index.php/aimagazine/article/view/566. Acesso em: 22 sep. 2024.