Bi-interpretability with $\mathbb{Z}$ and models of the complete elementary theories of $\text{SL}_n(\mathcal{O})$, $\text{T}_n(\mathcal{O})$ and $\text{GL}_n(\mathcal{O})$, $n\geq 3$. (arXiv:2004.03585v1 [math.GR]) http://arxiv.org/abs/2004.03585