1. Malaysian Institute of Chemical & Bioengineering Technology, Universiti Kuala Lumpur, 78000 Alor Gajah Melaka, Malaysia
2. Department of Mathematics, Faculty of Science & Technology, Universiti Malaysia Terengganu, 21030 Kuala Terengganu, Malaysia
3. Centre for Modelling & Data Analysis, School of Mathematical Sciences, Universiti Kebangsaan Malaysia, 43600 UKM Bangi Selangor, Malaysia