Three dimensional fermionic determinants, Chern-Simons and nonlinear   field redefinitions
  The three dimensional abelian fermionic determinant of a two component massive spinor in flat euclidean space-time is resetted to a pure Chern-Simons action through a nonlinear redefinition of the gauge field. 
D.G. Barci, V.E.R. Lemes, C. Linhares de Jesus, M.B.D. Silva Maia   Porto, S.P. Sorella, L.C.Q.Vilar