Khemis , RabahBouakkaz , Ahlème2025-07-152025-07-152022http://dspace.univ-skikda.dz:4000/handle/123456789/4971The key task of this paper is to investigate a nonlinear fourth-order delay differential equation. By virtue of the fixed point theory and the Green’s functions method, we establish some new results on the existence, uniqueness and continuous dependence on parameters of periodic solutions. In addition, an example is given to corroborate the validity of our main results. Up to now, no work has been carried out on this topic. So, the findings of this paper are new and complement the available works in the literature to some degree.enArticle