Ramadhani, S. W. “Influence of Service Quality Customer Loyalty And Trust In. Pos Indonesia (Persero) Lubukpakam”. Journal of Management Science (JMAS), vol. 1, no. 2, April, Apr. 2018, pp. 30-35, https://exsys.iocspublisher.org/index.php/JMAS/article/view/6.