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3. Shil’nikov, L.P. and Turaev, D.V., Simple Bifurcations Leading to Hyperbolic Attractors: Computational Tools of Complex Systems: 1, Comput. Math. Appl., 1997, vol. 34, nos. 2–4, pp. 173–193.
4. Shilnikov, L.P. and Turaev, D.V., A New Simple Bifurcation of a Periodic Orbit of ¡¡Blue Sky Catastrophe¿¿ Type, in Methods of Qualitative Theory of Differential Equations and Related Topics, Amer. Math. Soc. Transl. Ser. 2, vol. 200, Providence,R.I.: AMS, 2000, pp. 165–188.
5. Gavrilov, N. and Shilnikov, A., Example of a Blue Sky Catastrophe, in Methods of Qualitative Theory of Differential Equations and Related Topics, Amer. Math. Soc. Transl. Ser. 2, vol. 200, Providence,R.I.: AMS, 2000, pp. 99–105.