THUẦN, Hồ; THÀNH, Trần Thiên. SQL query expressed in relational calculus. <b>Journal of Computer Science and Cybernetics</b>, <i>[S. l.]</i>, v. 14, n. 4, p. 73–80, 2016. DOI: 10.15625/1813-9663/14/4/7976. Disponível em: https://jcc.vast.vn/jcc/article/view/7976. Acesso em: 4 nov. 2025.