Oky Sugarbo, Hill. Gendoet Hartono, and Bernadeta Subandini Astuti. “Identifikasi Awal Keberadaan Gunung Api Purba Gemawang, Ngadirojo, Wonogiri, Jawa Tengah”. ReTII00 (December 15, 2014). Accessed May 9, 2024. //journal.itny.ac.id/index.php/ReTII/article/view/1592.