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Source. Karamanlis, published p. 5, Proposition 5 (canonical PDF). The corresponding arXiv v1–v3 result is Proposition 3.3.

Statement. For every almost-regular simplex ZZ and every integer m≥2m\ge2, there is an mm-regular polygonal torus containing an isometric copy of ZZ. The polygon radii may differ.

Proof. By Lemma 4, the distance array of ZZ is realized by labeled points in a product Δ1×⋯×Δℓ\Delta_1\times\cdots\times\Delta_\ell of regular simplices. Matching labels gives an isometry from ZZ to those points. Write na=∣Δa∣n_a=|\Delta_a|. For the prescribed common order mm, Lemma 3 embeds each Δa\Delta_a into Tm,ranaT_{m,r_a}^{n_a} for a suitable ra>0r_a>0. Products of these maps preserve squared distances, since each product distance is the sum of the squared distances in its factors. Composing and restricting gives an embedding of ZZ into

∏a=1ℓTm,rana,\prod_{a=1}^{\ell}T_{m,r_a}^{n_a},

which is mm-regular. □\square

Use. In Proposition 11, the common order is chosen first by an approximation. This proposition can use exactly that order for the corrective factor; a common radius is unnecessary.