Seam C1A2 Group coal rank analysis in East Meranti PIT, Katanjung Village, Kapuas Regency based on proximate valuesIreine Ester Wowiling, Aang Panji Permana, Ronal Hutagalung, Galih Sagita and Frangky Friyanto LakoyMATEC Web Conf., 402 (2024) 03005DOI: https://doi.org/10.1051/matecconf/202440203005