EN
We consider first order neutral functional differential equations with multiple deviating arguments of the form
$(x(t)+Bx(t-δ))' = g₀(t,x(t)) + ∑_{k=1}^{n} g_{k}(t,x(t-τ_{k}(t))) + p(t)$.
By using coincidence degree theory, we establish some sufficient conditions on the existence and uniqueness of periodic solutions for the above equation. Moreover, two examples are given to illustrate the effectiveness of our results.