This issue is devoted to Professor Weigao Ge, a distinguished scientific personality in several aspects of the theory of ordinary and functional differential equations. He is recognized and respected throughout the mathematical world. He is a holder of numerous prizes and awards, among them we highlight the government allowance of the People Republic of China. He has published over 300 research papers, some of them being extensive and important works of his monographs. He has supervised 40 PhD students. All of them have already obtained the Doctorate of Science degree and have become leading personalities in their fields of research. This special issue is to celebrate his great achievements in the study of the qualitative theory of ordinary and functional differential equations.
Edited by: Ravi Agarwal, Hairong Lian and Jufang Zhao