1. School of Civil Engineering, Engineering Campus, Universiti Sains Malaysia, Seberang Perai Selatan, P. Pinang, Malaysia
2. Department of Civil Engineering, Kano University of Science and Technology, Wudil, Kano, Nigeria
3. School of Materials and Mineral Resources Engineering, Engineering Campus, Universiti Sains Malaysia, Seberang Perai Selatan, P. Pinang, Malaysia
4. School of Science and Engineering, University of Sunshine Coast, Sippy Downs, Australia