Sm. Soskin, NONLINEAR RESONANCE FOR THE OSCILLATOR WITH A NONMONOTONIC DEPENDENCEOF EIGENFREQUENCY ON ENERGY, Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics, 50(1), 1994, pp. 180000044-180000046
An alternative type of nonlinear resonance is reported. Its paradoxica
l peculiarity is demonstrated: an exact resonance between an external
periodic field and a free oscillation at some energy is not necessaril
y needed, unlike the conventional nonlinear resonance. Examples of phy
sical systems are given.