Homogeneous Hypercomplex Structures II - Coset Spaces of compact Lie   Groups
  We obtain a complete classification of hypercomplex manifolds, on which a compact group of automorphisms acts transitively.   The description of the spaces as well as the proofs of our results use only the structure theory of reductive groups, in particular the notion of "stem" of a reduced root system, introduced in the first paper of this series. 
George Dimitrov, Vasil Tsanov
math.DG math.GR