Existence and uniqueness for a degenerate parabolic equation with L-1-data

In this paper we study existence and uniqueness of solutions for the bounda ry-value problem, with initial datum in L-1(Omega), u(t) = div a(x, Du) in (0, infinity) x Omega, -partial derivative u/partial derivative eta(a) is an element of beta(u) on (0,infinity) x partial derivative Omega, u(x,0) = u(0) (x) in Omega, where a is a Caratheodory function satisfying the classical Leray-Lions hyp othesis, , is the Neumann boundary operator associated to a, Du the gradien t of u and beta is a maximal monotone graph in R x R with 0 is an element o f beta(0).