Windy Stevani Siahaan and Dendi Gusnadi 2024. Implementasi Standar Operasional Prosedur Telepon Operator di Sheraton Hotel Bandung. El-Mal: Jurnal Kajian Ekonomi & Bisnis Islam. 5, 9 (Sep. 2024), 4077 –. DOI:https://doi.org/10.47467/elmal.v5i9.4255.