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https://doi.org/10.1016/0022-0396(92)90076-Y

has been cited by the following article:

• TITLE: Infinite Subharmonic Solutions of the Forced Relativistic Oscillators

  AUTHORS: Zaihong Wang, Tiantian Ma

  KEYWORDS: Relativistic Oscillator, Subharmonic Solution, Poincaré-Birkhoff Fixed Point Theorem

  JOURNAL NAME: Journal of Applied Mathematics and Physics, Vol.7 No.7, July 19, 2019

  ABSTRACT: In this paper, we study the multiplicity of subharmonic solutions of the nonlinear differential equation of the forced relativistic oscillators. By using the generalized Poincaré-Birkhoff fixed point theorem, we prove that the equation has infinite subharmonic solutions provided that g satisfies at most linear growth condition.