  Let G be the Tate module of a p-divisble group H over a perfect field k of
characteristic p. A theorem of Scholze-Weinstein describes G (and therefore H
itself) in terms of the Dieudonne module of H; more precisely, it describes
G(C) for "good" semiperfect k-algebras C (which is enough to reconstruct G).
  In these notes we give a self-contained proof of this theorem and explain the
relation with the classical descriptions of the Dieudonne functor from
Dieudonne modules to p-divisible groups.
