Conformal Differential Operator in Embedding Space and its Applications
  We develop techniques useful for obtaining conformal blocks in embedding space. We construct a unique differential operator in embedding space and use it to construct a function that will be an important ingredient in assembling conformal blocks. We show a number of relations that the components of conformal blocks satisfy and find invariance of our expressions under the dihedral group. 
Jean-Fran\c{c}ois Fortin, Witold Skiba
hep-th