Electronic Journal of Qualitative Theory of Differential Equations
2016, No. 9, 1–9; doi: 10.14232/ejqtde.2016.1.9 https://www.math.u-szeged.hu/ejqtde/

Limit cycles for a class of polynomial
differential systems
Jianyuan Qiao and Shuliang Shui B
College of Mathematics, Physics and Information Engineering, Zhejiang Normal University,
Jinhua, 321004, P.R. China
Received 10 August 2015, appeared 9 February 2016
Communicated by Gabriele Villari，

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