Couplings of heavy mesons with soft pions in QCD
  QCD sum rules are used to calculate the couplings of heavy-light quark pseudoscalar and vector mesons ($D, D^*$ and $B, B^*$) with soft pions, both for finite and infinitely heavy quark mass. The couplings are also computed in the framework of a QCD relativistic potential model; in this approach the relativistic corrections due to the light quark are relevant. 
P.Colangelo