A. S. Pratama, W. . Yuliawati, D. Hatta, and S. Shalahuddin, “THE IMPACT OF YEN EXCHANGE RATE, COAL REFERENCE PRICE, LNG PRICE, AND COAL PRODUCTION ON INDONESIA COAL EXPORTS TO JAPAN”, Jurnal Hasil Penelitian/JEINSA, vol. 4, no. 2, pp. 129–141, Oct. 2025.