Cheng, Sui SunZhang, Guang2020-06-302020-06-302001-09-04Cheng, S. S., & Zhang, G. (2001). Existence of positive periodic solutions for non-autonomous functional differential equations. <i>Electronic Journal of Differential Equations, 2001</i>(59), pp. 1-8.1072-6691https://hdl.handle.net/10877/11930We establish the existence of positive periodic solutions for a first-order differential equation with periodic delay. For this purpose, we use the fixed point theorem proved by Krasnoselskii.Text8 pages1 file (.pdf)enAttribution 4.0 InternationalPositive periodic solutionsConeDelayArticle