1. Department of Geological Engineering, Universitas Gadjah Mada, Yogyakarta, Indonesia
2. School of GeoSciences, The University of Edinburgh, Edinburgh, UK
3. Department of Geological Engineering, Universitas Pembangunan Nasional Veteran, Yogyakarta, Indonesia
4. Research Center for Geological Resources, National Research and Innovation Agency, Indonesia
5. Department of Geology, Aristotle University of Thessaloniki, Thessaloniki, Greece
6. Independent Geologist, Jl. Hj Naim, Jakarta, Indonesia