1. Faculty of Fundamental Science, Industrial University of Ho Chi Minh City, Ho Chi Minh City, Vietnam
2. Department of Mathematics and Statistics, Auburn University, USA
3. School of Mathematics, Iran University of Science and Technology, Narmak, Tehran
4. Division of Applied Mathematics, Science and Technology Advanced Institute, Van Lang University, Ho Chi Minh City, Vietnam
5. Faculty of Technology, Van Lang University, Ho Chi Minh City, Vietnam