On the asymptotic behaviour of solutions of differential equations in a banach space

The purpose of this paper is to consider the asymptotic behaviour of solutions of the initial value problemdu/dt = Au + F(t, u) u(t0) =u0t ≧ t0 in a Banach spaceX with an unbounded, nonlinear operatorA. Conditions are given which guarantee that for sufficiently smallu0 the solutions converge to zero. The problem of asymptotic stability is also treated. In the last section there are applications to partial differential equations.