共 50 条
- [38] Existence of periodic solutions for Lienard equations with finite delay CHINESE SCIENCE BULLETIN, 1997, 42 (14): : 1145 - 1149
- [40] An approximation method for the existence of periodic solutions to systems with delay ZEITSCHRIFT FUR ANGEWANDTE MATHEMATIK UND MECHANIK, 1996, 76 : 205 - 208