Uniqueness of the measure of maximal entropy for geodesic flows on certain manifolds without conjugate points

We prove that for closed surfaces M with Riemannian metrics without conjugate points and genus ?2 the geodesic flow on unit tangent bundle T1M has a unique measure of maximal entropy. Furthermore, this is fully supported T1M, limiting distribution orbits, mixing respect to measure. formulate conditions under which result extends higher dimensions.