reserve X for non empty TopSpace;
reserve X for non empty TopSpace;
reserve X for non empty TopSpace,
  X0 for non empty maximal_Kolmogorov_subspace of X;

theorem Th26:
  for E being Subset of X, F being Subset of X0 st F = E holds (
  Stone-retraction(X,X0))" (F) = MaxADSet(E)
by Def9,Lm6;
