Trace theorems in harmonic function spaces on (R^n+1)^m,multiplier   theorems and related problems
  We introduce and study properties of certain new harmonic function spaces on products of upper half-spaces.Norm estimates for the so-called expanded Bergman projections are obtained.Sharp theorems on multipliers acting on certain Sobolev type spaces of harmonic functions on the unit ball are also obtained 
Milos Arsenovic, Romi F. Shamoyan
math.FA