中国科学院数学与系统科学研究院期刊网
Existence of Periodic Solutions for Second Order Nonlinear Neutral Delay Equations
Gen Qiang WANG(1),Ju Rang YAN(
Acta Mathematica Sinica, Chinese Series . 2004, (2): 379 -384 .  DOI: 10.12386/A2004sxxb0048