Christantyo, James. “KUALITAS PRODUK DAN LAYANAN TERHADAP KEPUASAN PELANGGAN BLACK KAWA COFFEE SURABAYA”. Jurnal Performa: Jurnal Manajemen dan Start-up Bisnis 5, no. 1 (May 1, 2020): 72–78. Accessed March 12, 2026. https://journal.uc.ac.id/index.php/performa/article/view/1304.