Department of Mathematics, College of Computer Science and Mathematics, Mosul University, Mosul, Iraq
Department of Mathematics, College of Computer Science and Mathematics, Mosul University, Mosul, Iraq
Copyright © 2019 Waleed Al-Hayani, Rasha Fahad et al. This is
an open access article distributed under the Creative Commons Attribution
License, which permits unrestricted use, distribution, and reproduction in any
medium, provided the original work is properly cited.