  The authors reexamine the two-dimensional model of massive fermions
interacting with a massless pseudoscalar field via axial-current-pseudoscalar
derivative coupling. Performing a canonical field transformation on the Bose
field algebra the model is mapped into the Thirring model with an additional
vector-current-scalar-derivative interaction (Schroer-Thirring model). The
complete bosonized version of the model is presented. The bosonized composite
operators of the quantum Hamiltonian are obtained as the leading operators in
the Wilson short distance expansion.
