Laiya, Satrio P., Johny A. F. Kalangi, and Danny D. S. Mukuan. “The Effect of Service Quality and Product Quality on Customer Satisfaction at Billy Coffee House in the Mega Mas Area of Manado”. Productivity 4, no. 5 (July 25, 2023): 564–578. Accessed March 21, 2026. https://ejournal.unsrat.ac.id/v3/index.php/productivity/article/view/49990.