1. Department of Information Science, College of Humanities and Sciences, Nihon University, Setagaya-ku, Tokyo, Japan.
2. Department of Mathematics and Computer Science, Transilvania University of Braşov, Braşov, 500091, Romania.
3. Department of Mathematics, Mashhad Branch, Islamic Azad University, Mashhad, Iran.
4. Department of basic sciences, Princess Sumaya University For Technology, Al Jubaiha, Amman 11941, Jordan