1. Anyang Vocational and Technical College, Foreign Affairs Office of Scientific Research, Anyang, Henan 455001, China
2. Department of Mathematics, Government College University, Katehrey Road, Lahore 54000, Pakistan
3. Department of Mathematics, Khon Kaen University, Khon Kaen 40002, Thailand
4. Department of Mathematics, Faculty of Science, Khon Kaen University, Khon Kaen 40002, Thailand