Rahmadi. “Characteristics of Silica in Mountain Area Tapa and Sorrounding Areas of Tulang Bawang Regency Lampung Province”. Journal of Engineering and Scientific Research 7, no. 2 (October 8, 2025): 83–96. Accessed January 15, 2026. https://jesr.eng.unila.ac.id.121-50-32-50.cpanel.site/index.php/ojs/article/view/204.