中国科学院数学与系统科学研究院期刊网
Multiple Positive Solutions for Nonlinear Second-order Delay Differential Equations
WANG Huimin, MENG Xiangwang, JIANG Wei
Acta Mathematicae Applicatae Sinica . 2013, (3): 566 -572 .  DOI: 10.12387/C2013052