We study second-order ordinary differential equations of Newtonian type. The forcing terms under consideration are the product of a nonlinearity which is singular at the origin with an indefinite weight. Under some additional assumptions we show the existence of periodic solutions.
"Periodic solutions of singular equations." Topol. Methods Nonlinear Anal. 47 (1) 55 - 72, 2016. https://doi.org/10.12775/TMNA.2015.087