Heavy Quark Effective Theory on the Light Front
  The light-front heavy quark effective theory is derived to all orders in $1/m_Q$. In the limit $m_Q\rightarrow \infty$, the theory exhibits the familiar heavy quark spin-flavor symmetry. This new formalism permits a straightforward canonical quantization to all orders in $1/m_Q$; moreover, higher order terms have rather simple operator structures. The light-front heavy quark effective theory can serve as an useful framework for the study of non-perturbative QCD dynamics of heavy hadron bound states. 
Wei-Min Zhang, Guey-Lin Lin and Chi-Yee Cheung