Author(s)

An-Min Mao, Miao-Miao Yang

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We study the multiple existence of periodic solutions for a second-order non-autonomous dynamical systems (1). Using the method of invariant sets of descending flow and chain of rings theorem, we obtain the existence of seven -periodic solutions.

Critical Point, Invariant Sets of Descending Flow, (PS) Condition

A. Mao and M. Yang, "Periodic Solutions to Non-Autonomous Second-Order Dynamical Systems," Advances in Pure Mathematics, Vol. 1 No. 3, 2011, pp. 90-94. doi: 10.4236/apm.2011.13020.