Rahmadi. “Characteristics of Silica in Mountain Area Tapa and Sorrounding Areas of Tulang Bawang Regency Lampung Province”. Journal of Engineering and Scientific Research, vol. 7, no. 2, Oct. 2025, pp. 83-96, https://www.jesr.eng.unila.ac.id.121-50-32-50.cpanel.site/index.php/ojs/article/view/204.