General parabolic initial-boundary value problems in H\"ormander spaces
  We investigate a general nonhomogeneous parabolic initial-boundary value problem in some anisotropic H\"ormander inner product spaces. We prove that the operators corresponding to this problem are isomorphisms between appropriate H\"ormander spaces. As an application of this result, we establish a theorem on the local increase in regularity of solutions to the problem. 
V. M. Los, V. A. Mikhailets, A. A. Murach
math.AP