1. Department of Mathematics, College of Basic Education, University of Duhok, Duhok 42001, Iraq
2. Department of Mathematics, College of Computer Science and Mathematics, University of Mosul, Mosul 41001, Iraq
3. Department of Computer Science, College of Science, Cihan University-Duhok, Duhok 42001, Iraq
4. Department of Mathematics, Faculty of Science, University of Zakho, Zakho 42002, Iraq