f Perfecting the migrated-based travel-time reformulation of the 2D seismic inversion problem

In this work, we present two steps toward the implementation of the Migrated-Based Travel-Time (MBTT) reformulation for the determination of 2D background velocities: we first indicate how to define the propagator/reflector unknowns required in MBTT; then we give a very simple a priori guess of the new reflector unknowns