Monotonicity of the period map of a non-Hamiltonian center.
Uniqueness of limit cycles bounded by two invariant parabolas
In this paper we consider a class of cubic polynomial systems with two invariant parabolas and prove in the parameter space the existence of neighborhoods such that in one the system has a unique limit cycle and in the other the system has at most three limit cycles, bounded by the invariant parabolas.
Cuadrados mágicos concéntricos.
Coexistence of small and large amplitude limit cycles of polynomial differential systems of degree four
A class of degree four differential systems that have an invariant conic , , is examined. We show the coexistence of small amplitude limit cycles, large amplitude limit cycles, and invariant algebraic curves under perturbations of the coefficients of the systems.
Page 1