中国科学院数学与系统科学研究院期刊网
AMS
Lie Symmetries of Quasihomogeneous Polynomial Planar Vector Fields and Certain Perturbations
Javier CHAVARRIGA, Isaac A. GARCÍA
Acta Mathematica Sinica . 2005, (1): 185 -192 .  DOI: 10.1007/s10114-004-0445-9