SUWARNA, Nana. Permian Mengkarang coal facies and environment, based on organic petrology study. Indonesian Journal on Geoscience, [S. l.], v. 1, n. 1, p. 1–8, 2006. DOI: 10.17014/ijog.1.1.1-8. Disponível em: https://ijog.geologi.esdm.go.id/index.php/IJOG/article/view/3. Acesso em: 7 jun. 2025.