### Nonlinear Elliptic Equations with Lower Order Terms and Symmetrization Methods

We consider the homogeneous Dirichlet problem for nonlinear elliptic equations as $$-\mathrm{div}a(x,\nabla u)=b(x,\nabla u)+\mu $$ where $\mu $ is a measure with bounded total variation. We fix structural conditions on functions $a$, $b$ which ensure existence of solutions. Moreover, if $\mu $ is an ${L}^{1}$ function, we prove a uniqueness result under more restrictive hypotheses on the operator.