A One-level Additive Schwarz Preconditioner for a Discontinuous   Petrov-Galerkin Method
  Discontinuous Petrov-Galerkin (DPG) methods are new discontinuous Galerkin methods with interesting properties. In this article we consider a domain decomposition preconditioner for a DPG method for the Poisson problem. 
Andrew T. Barker, Susanne C. Brenner, Eun-Hee Park and Li-Yeng Sung
math.NA