Smart Costing Based on Activity-Based Costing in Improving the Operational Efficiency of Alawi Catering MSME in Nunukan Regency. - Suryaningsih; Usman, Ferawati; Nursia; Karunia, Erick; Pinjaman, Saizal (Jurnal Nusantara Aplikasi Manajemen Bisnis, 2026)