Charmed Mesons and Charmonia: Three-Meson Strong Couplings
  Revisiting the strong couplings of three mesons, each of which involves at least one charm quark, proves clear disaccord between quark-model and QCD sum-rule results. 
Wolfgang Lucha, Dmitri Melikhov, Hagop Sazdjian, Silvano Simula
hep-ph nucl-th