| Affiliation: | 1. Faculty of Mathematics, University of Cluj, R-3400 Cluj, CP 253, Romania;2. Faculty of Pharmacy, University of Medicine and Pharmacy “Iuliu Hatieganu”, Cluj, Romania;1. Department of Mathematics and Physics, Hefei University, Hefei 230601, China;2. School of Mathematics and Statistics, Huazhong University of Science and Technology, Wuhan 430074, China;1. Department of Mathematics, State University of Maringá, 87020-900, Maringá, PR, Brazil;2. Center of Exact Sciences and Technology, Federal University of Acre, 69920-900, Rio Branco, AC, Brazil |
