Method for calculating director symbols in a free context grammar. Journal Prospectiva, [S. l.], v. 18, n. 2, 2020. DOI: 10.15665/rp.v18i2.2289. Disponível em: https://ojs.uac.edu.co/index.php/prospectiva/article/view/2289. Acesso em: 29 sep. 2026.