IMTIYAZ, A. R. .; PUTRA, A. R. K. .; KARO, E. Z. K. .; NAWAWI, F. .; TARINA, D. D. Y. . Wanprestasi Dalam Jual Beli Batubara. Indonesian Research Journal on Education, [S. l.], v. 5, n. 4, p. 14 –, 2025. DOI: 10.31004/irje.v5i4.2818. Disponível em: https://irje.org/irje/article/view/2818. Acesso em: 6 oct. 2026.