Puspita Sari R, Laksmi Rithmaya C. Evaluation of The Implementation of Standard Operating Prosedures (SOP) In Term Of Excellent Service By Customer Service Officer At Grapari Garuda Telkomsel Surabaya. IJSE [Internet]. 2025 Aug. 8 [cited 2025 Aug. 19];5(3):413-6. Available from: https://ijsenet.com/index.php/IJSE/article/view/200