EHIKIOYA, Sylvanus A. A formal perspective to modelling electronic commerce transactions. Revista Colombiana de Computación, [S. l.], v. 2, n. 2, p. 1–20, 2001. Disponível em: https://revistasunabeduco.biteca.online/index.php/rcc/article/view/1113. Acesso em: 23 ago. 2025.