The article is light on details and I assume that this is accounted for in the paper or problem definition, but there does seem to be a way to make a Mobius str

The article is light on details and I assume that this is accounted for in the paper or problem definition, but there does seem to be a way to make a Mobius strip-like construction from a square surface: https://math.stackexchange.com/a/734261 https://math.stackexchange.com/a/734261 Like the author of the answer, I am unsure whether this counts.