Before revision:  The subshift X_0 \Omega_0 is proper due to some horizontal fracture of 0's or 1's in tilings in \Omega_0 and we believe that \Omega_0\setminus X_0 is a null set . Algorithms are provided to find markers, recognizable substitutions and sheering topological conjugacy from a set of Wang tiles.
After revision:  The subshift X_0 tilings as we believe that \Omega_0\setminus X_0 is a null set . Algorithms are provided to find markers, recognizable substitutions and sheering topological conjugacy from a set of Wang tiles.