The Dynamical Retardation Corrections to the Mass Spectrum of Heavy   Quarkonia
  A new version for the relativistic generalization of the wide class of static quark--antiquark confining potentials is suggested. The comparison of this approach with other ones, known in literature, is considered. With the use of Logunov--Tavkhelidze quasipotential approach the first--order retardation corrections to the heavy quarkonia mass spectrum are calculated. As expected, these corrections turn out to be small for all low--lying heavy meson states. 
Teimuraz Kopaleishvili and Akaki Rusetsky