GOVIND, A. Impact of Value Added Services by Mobile Network Companies On Customer Retention. International Journal of Research in Engineering, Science and Management, [S. l.], v. 4, n. 6, p. 35–38, 2021. Disponível em: https://journal.ijresm.com/index.php/ijresm/article/view/793. Acesso em: 16 oct. 2025.