LUBIS, P. N.; AZHMY, M. F. Improving Service Quality as an Effort to Grow Customer Loyalty. Jurnal Mantik, [S. l.], v. 5, n. 3, p. 2108-2116, 2021. Disponível em: https://iocscience.org/ejournal/index.php/mantik/article/view/1865. Acesso em: 19 apr. 2026.