Semi-classical theory of magnetic quantum oscillations in a   two-dimensional multiband canonical Fermi liquid
  The semi-classical Lifshitz-Kosevich (LK) description of quantum oscillations is extended to a multiband two-dimensional Fermi liquid with a constant number of electrons. The amplitudes of novel oscillations with combination frequencies, recently predicted and observed experimentally, are analytically derived and compared with the single-band amplitudes. The combination amplitudes decay with temperature exponentially faster than the standard harmonics, and this provides a valuable tool for their experimental identification. 
A.S. Alexandrov and A.M. Bratkovsky