Institution: | 1. Department of Mathematics, Faculty of Science, Naresuan University, Phitsanulok 65000, Thailand;2. Department of Mathematics, Faculty of Science, King Mongkut’s University of Technology Thonburi (KMUTT), Bangmod, Thungkru, Bangkok 10140, Thailand;3. Centre of Excellence in Mathematics, CHE, Si Ayutthaya Road, Bangkok 10400, Thailand |