1. School of Industrial Technology, University Sains Malaysia, Pulau Pinang, Malaysia;
2. School of Industrial Technology, Centre for Global Sustainability Studies (CGSS), University Sains Malaysia, Pulau Pinang, Malaysia;
3. Department of Hydrology, Banaras Hindu University, Varanasi, India;
4. National Institute of Hydrology, Roorkee, India;
5. Department of Geology, University of Malaya, Kuala Lumpur, Malaysia;
6. School of Physics, University Sains Malaysia, Pulau Pinang, Malaysia;
7. Department of Earth Science, Indian Institute of Technology, Roorkee, India