1. Faculty of Social Sciences and Political Sciences, Airlangga University, Surabaya, Indonesia;
2. Global Geophysics Research Group, Faculty of Mining and Petroleum Engineering, Bandung Institute of Technology, Bandung, Indonesia;
3. Faculty of Engineering, Maranatha Christian University, Bandung, Indonesia;
4. Faculty of Human Ecology, Bogor Agricultural University, Bogor, Indonesia;
5. Geological Engineering Department, Faculty of Engineering, Gadjah Mada University, Yogyakarta, Indonesia