The broken scattering relation consists of the total lengths of broken geodesics that
start from the boundary, change direction once inside the manifold, and propagate to
the boundary. We show that if two reversible Finsler manifolds satisfying a convex
foliation condition have the same broken scattering relation, then they are isometric.
This implies that some anisotropic material parameters of the earth can
be in principle reconstructed from single scattering measurements at the
surface.