1. Department of Mathematical Sciences, Yazd University, 89195-741, Yazd, Iran.
2. Department of Computer Science, University of Bojnord, Bojnord, Iran.
3. Novosibirsk State University, Pirogova str. 2, Novosibirsk, 630090, Russia
4. Sobolev Institute of Mathematics, Ak. Koptyug av. 4, Novosibirsk, 630090, Russia