THE EFFECT OF SERVICE QUALITY AND PRODUCT QUALITY ON CUSTOMER LOYALTY IN RISOL GOGO UMKM IN MEDAN CITY. ICOERESS [Internet]. 2026 Jul. 14 [cited 2026 Sep. 27];2(2):755-61. Available from: https://icoeress.pasca.uinjambi.ac.id/index.php/icoeress/article/view/182