MARTADI; PAMBUDI, Setyo; VERDIANSYAH, Okki. Optimizing of Drill Hole Spacing For Coal Resources Classification in Kelay Blok 3 Area, Labanan Formation, Berau Regency, East Kalimantan. International Journal of Basic and Applied Sciences, [S. l.], v. 14, n. 8, p. 667–675, 2026. DOI: 10.14419/nbt0tq29. Disponível em: https://www.sciencepubco.com/index.php/IJBAS/article/view/37050.. Acesso em: 7 jan. 2026.