Non-perturbative tests of HQET in small-volume quenched QCD
  We quantitatively investigate the quark mass dependence of current matrix elements and energies, calculated over a wide range of quark masses in the continuum limit of small-volume quenched lattice QCD. By a precise comparison of these observables as functions of the heavy quark mass with the predictions of HQET we are able to verify that their large quark mass behaviour is described by the effective theory. 
Jochen Heitger, Andreas Juttner, Rainer Sommer and Jan Wennekers