Department of Mathematics, Faculty of Science, Tanta University, Tanta, Egypt
Mathematics and Statistics Department, College of Science, Taibah University, Yanbu, KSA
Mathematics and Statistics Department, Canal Higher Institute of Engineering and Technology, Suez, Egypt
Copyright © 2019 A. A. M. Teamah, W. A. Afifi 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.