Perdanie, E. P., R. Rahmadani, H. Oktaviannoor, and T. Alawiyah. “Pemanfaatan Arang Aktif Tongkol Jagung (Zea Mays) Dalam Menurunkan Kesadahan Pad Air Sumur Di Kabupaten Katingan: Ultilization of Corn COB Activated Charcoal (Zea Mays) in Reducing the Hardness of Well Water in Katingan Regency”. Jurnal Surya Medika (JSM), vol. 10, no. 3, Dec. 2024, pp. 88-94, doi:10.33084/jsm.v10i3.8969.