Tunc, C.2025-05-102025-05-1020090716-091710.4067/S0716-091720090002000022-s2.0-84983575330https://doi.org/10.4067/S0716-09172009000200002https://hdl.handle.net/20.500.14720/6551In this paper, it is investigated the existence of periodic solutions to the nonlinear third order differential equation: x‴ + c2(t)x″ + c1(f)x′ + f(t, x) = p(t, x, x′, x″). The Leray-Schauder principle is used to show the existence of periodic solutions of this equation.eninfo:eu-repo/semantics/openAccessNonlinear Third Order Differential EquationPeriodic SolutionArticle282N/AQ3125132