GRADIENT ESTIMATES AND COMPARISON PRINCIPLE FOR SOME NONLINEAR ELLIPTIC EQUATIONS.

We consider a class of Dirichlet boundary problems for nonlinear elliptic equations with a first order term. We show how the summability of the gradient of a solution increases when the summability of the datum increases. We also prove comparison principle which gives in turn uniqueness results by strenghtening the assumptions on the operators. [ABSTRACT FROM AUTHOR]