Dea Pravita Gunawan, Endang Murti, Bambang Martin Baru. STANDARD OPERATING PROCEDURE (SOP) FOR THE IMPLEMENTATION OF THE COLLECTION UNIT FUNCTION AT PT. KERETA API INDONESIA (PERSERO) DAOP 7 MADIUN: Standar Operasional Prosedur (SOP) Pelaksanaan Fungsi Unit Penagihan di PT. Kereta Api Indonesia (PERSERO) DAOP 7 Madiun. JS [Internet]. 2026 Apr. 30 [cited 2026 May 4];10(2):686-92. Available from: https://ejournal.unibabwi.ac.id/index.php/santhet/article/view/7738