Prayitna, Yusri, Widya Utama, and Dwa Desa Warnan. “Landslide Analysis Using Seismic Refraction Tomography And MASW: A Case Study in Ponorogo, East Java, Indonesia”. IPTEK The Journal of Engineering 5, no. 2 (September 2, 2025): 43–47. Accessed January 29, 2026. https://journal.its.ac.id/index.php/joe/article/view/8044.