ภู่พงษ์วัฒนา ศ. Gray Market: Opportunities for Producers and Distributors. Journal of Humanities and Social Sciences, Rajapruk University, [S. l.], v. 2, n. 2, p. 1–11, 2016. Disponível em: https://so03.tci-thaijo.org/index.php/rpu/article/view/112405. Acesso em: 2 may. 2024.