1. School of Computer Science, Chengdu University, Chengdu, China
2. Department of Mathematics, COMSATS University Islamabad, Attock Campus, Attock, Pakistan
3. Department of Mathematics, Faculty of Applied Science, King Mongkut’s University of Technology North Bangkok, Bangkok 10800, Thailand
4. Mathematics Department, Faculty of Science and Technology, Suan Dusit University, Bangkok 10300, Thailand