Minkowski-type and Alexandrov-type theorems for polyhedral herissons
  Classical H.Minkowski theorems on existence and uniqueness of convex polyhedra with prescribed directions and areas of faces as well as the well-known generalization of H.Minkowski uniqueness theorem due to A.D.Alexandrov are extended to a class of nonconvex polyhedra which are called polyhedral herissons and may be described as polyhedra with injective spherical image. 
Victor Alexandrov (Sobolev Institute of Mathematics, Novosibirsk,   Russia)