  If $\mathcal{Z}$ is a dp-minimal expansion of a discrete ordered abelian
group $(Z,<,+)$ and $\mathcal{Z}$ does not admit a nontrivial definable convex
subgroup then $\mathcal{Z}$ is interdefinable with $(Z,<,+)$ and $(Z,<,+)$ is
elementarily equivalent to $(\mathbb{Z},<,+)$.
