THÁI, N. X. Relation scheme that has a unique key. Journal of Computer Science and Cybernetics, [S. l.], v. 17, n. 4, p. 66–68, 2012. DOI: 10.15625/1813-9663/17/4/2293. Disponível em: https://vjs.ac.vn/index.php/jcc/article/view/2293. Acesso em: 5 may. 2024.