Wage Prakoso, T., Wahyu Dalio, D., Steven, A., & G. Hartono, H. (2016). Studi Awal Keberadaan Gunung Api Purba Tulakan-Ketro, Pacitan, Jawa Timur. ReTII. Retrieved from //journal.itny.ac.id/index.php/ReTII/article/view/171