Oscillation theorems for neutral differential equations with the quasi-derivatives

The authors study the n-th order nonlinear neutral diierential equations with the quasi { derivatives Lnx(t)+(?1) r P (t)x(g(t))]+Q(t)f(x(h(t))) = 0; where n 2; r 2 f1;2g; and = 1: There are given suucient conditions for solutions to be either oscillatory or they converge to zero.