Candra, Ricki, Nelly Astuti, dan Fery Panjaitan. “ANALISIS PENGARUH KUALITAS PRODUK, HARGA, DAN PROMOSI TERHADAP LOYALITAS PELANGGAN BELFOODS DI PANGKALPINANG”. JURNAL PROGRESIF MANAJEMEN BISNIS 9, no. 1 (April 1, 2022): 1–6. Diakses November 21, 2024. https://e-jurnal.stie-ibek.ac.id/index.php/JIPMB/article/view/161.