Anomalous amplitudes in a thermal bath
  I review the implications of the axial anomaly in a thermal bath. I assume that the Adler-Bardeen theorem applies at nonzero temperature, so that the divergence of the axial current remains is independent of temperature. Nevertheless, I argue that while the anomaly doesn't change with temperature, ``anomalous'' mesonic couplings do. This is verified by explicit calculations in a low temperature expansion, and near the chiral phase transition. 
R. D. Pisarski, T. L. Trueman, and M. H. G. Tytgat