Oscillation behavior of nth order neutral differential equations with continuous delay

We consider the nth order nonlinear neutral differential equation of the form x(t)+ b a p(t,μ)x τ(t,μ) dμ (n) +λ d c q(t, ξ)f x σ(t,ξ) dξ = h(t). In this paper, we obtain sufficient conditions which ensure that all solutions are either oscillatory or limt→∞|x(t)|=∞ or else lim inft→∞|x(t)| = 0.  2003 Elsevier Inc. All rights reserved