Oscillation of higher-order neutral partial functional differential equations

Some sufficient conditions are established for the oscillation of higher-order neutral partial functional differential equations of the form partial derivative(n)/partial derivativet(n) [u(x,t) - p(t)u(x, t - tau)] = a(t)Deltau(x, t) + Sigma(k=1)(s) a(k)(t)Deltau(x, t - rho(k)(t)) -q(x, t)u(x, t) - Sigma(j=1)(m) q(j)(x, t)u(x, t - sigma(j)(t)), (x,t) is an element of Omega x [0, infinity) equivalent to G, where n greater than or equal to 1 is an odd integer, Omega is a bounded domain in R-N with a piecewise smooth boundary partial derivativeOmega, and Delta is the Laplacian in Euclidean N-space R-N. (C) 2003 Elsevier Science Ltd. All rights reserved.