Scaling in the Integer Quantum Hall Effect: interactions and low   magnetic fields
  Recent developments in the scaling theory of the integer quantum Hall effect are discussed. In particular, the influence of electron-electron interactions on the critical behavior are studied. It is further argued that recent experiments on the disappearance of the quantum Hall effect at low magnetic fields support rather than disprove the scaling theory, when interpreted properly. 
Bodo Huckestein, Michael Backhaus