Chinese Science Bulletin

, Volume 42, Issue 14, pp 1157–1161 | Cite as

Conditions for origin to be a center and the bifurcation of limit cycles in a class of cubic systems

  • Jiehua Zhu
  • Siming Zhu


center fine focus focal value limit cycle symbolic computation 


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    Zhu Siming, Zhu Jiehua, On the problem of distinguishing between a focus and a center for plane cubic systems,Ordinary Differential Equations Theory and its Applications (in Chinese), Beijing: Science Press, 1992, 222–222.Google Scholar
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    Kukles, I. S., Sur quelques cas de distinction entre un foyer et un centre,Dokl. Akad. Nauk. SSSR, 1944, 42: 208–211.Google Scholar

Copyright information

© Science in China Press 1997

Authors and Affiliations

  • Jiehua Zhu
    • 1
  • Siming Zhu
    • 1
  1. 1.Department of MathematicsZhongshan UniversityGuangzhouChina

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