Affiliation: | 1. Department of Optimization and Control Theory, Institute of Mathematics, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet road, Hanoi, Vietnam 2. Faculty of Information Technology, National Institute of Education Management, 31 Phan Dinh Giot, Hanoi, Vietnam 3. Faculty of Mathematics, University of Duisburg-Essen, Thea-Leymann-Stra?e 9, 45127?, Essen, Germany
|