A homological approach to singular reduction in deformation quantization
  We use the method of homological quantum reduction to construct a deformation quantization on singular symplectic quotients in the situation, where the coefficients of the moment map define a complete intersection. Several examples are discussed, among others one where the singularity type is worse than an orbifold singularity. 
Martin Bordemann, Hans-Christian Herbig, Markus J. Pflaum