Taher S. Hassan received his Bachelor’s degree in 1997, Master’s degree 2003 and Ph.D. degree in 2006 from Mansoura University, Egypt. He visited the University of Nebraska-Lincoln, USA, from 2007 until 2009. Now, he is an associate professor of mathematics at Mansoura University and Hail University. His research focuses on time scales, dynamic equations, differential equations, and difference equations.