Polar rotation angle identifies elliptic islands in unsteady dynamical systems

@article{Farazmand2015PolarRA,
  title={Polar rotation angle identifies elliptic islands in unsteady dynamical systems},
  author={Mohammad Farazmand and George Haller},
  journal={Physica D: Nonlinear Phenomena},
  year={2015},
  volume={315},
  pages={1-12}
}

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