Mean oscillation gradient estimates for elliptic systems in divergence form with VMO coefficients

We consider gradient estimates for H1 solutions of linear elliptic systems in divergence form ∂α(Aαβij∂βuj)=0. It is known that the Dini continuity of coefficient matrix A=(Aαβij) is essential for the differentiability of solutions. We prove the following results: (a) If A satisfies a condition sli...