On a MUltilayered CLOSED INVARIANT CURVE in non-invertible maps
The paper describes the mechanism for the formation of closed invariant curves that are formed as layered structures of several sets of interlacing manifolds each with their associated stable or unstable resonance modes. Such invariant curves can arise, for instance, if the saddle cycle on a «simple resonance curves» undergoes period-doubling or pitchfork bifurcations transversely to the circumference of the closed curve.