Sugeng Sapto Surjono,
Department of Geological Engineering, Faculty of Engineering, Universitas Gadjah Mada, Yogyakarta 55281,,
Indonesia
Mohd. Shafeea Leman,
Geology, School of Environmental and Natural Resource Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor,,
Malaysia
Kamal Roslan Mohamed,
Geology, School of Environmental and Natural Resource Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor,,
Malaysia
Che Aziz Ali,
Geology, School of Environmental and Natural Resource Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor,,
Malaysia