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Qualitative analysis of phase--portrait for a class of planar vector fields via the comparison method

Timoteo Carletti·Lilia Rosati·Gabriele Villari
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Abstract

The phase--portrait of the second order differential equation: $$\ddot x+\sum_{l=0}^nf_l(x) \dot x^l=0 ,$$ is studied. Some results concerning existence, non--existence and uniqueness of limit cycles are presented. Among these, a generalization of the classical Massera uniqueness result is proved.

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Timoteo Carletti, Lilia Rosati, Gabriele Villari. 2004-11-02. Qualitative analysis of phase--portrait for a class of planar vector fields via the comparison method. https://arxiv.org/abs/math/0411042

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