中国科学院数学与系统科学研究院期刊网
General Center Conditions and Bifurcation of Limit Cycles for a Planar Differential System
DU Chaoxiong, LIU Yirong
Acta Mathematicae Applicatae Sinica . 2014, (1): 69 -77 .  DOI: 10.12387/C2014007