Restoration of the residue factorizability in the bound-state pole by   instanton-antiinstanton configurations
  The instanton-antiinstnton contributions to the $q\overline{q}$ bound state pole in the four-point Green function in the Schwinger Model are calculated. It is shown that these configurations, thanks to the cancellation of all unwanted terms, are responsible for the restoration of the perfect factorizability of the residue. 
Tomasz Radozycki