[Design of Marci Letter]

[ReneZ]

I am guessing that paper book sizes were somewhat standard ("folio", "quarto", "octavo", etc.),

These terms are used equally for parchment manuscripts, and refer to the fraction of a full hide.
Still, there was no standard. Folio, Quarto, Octavo can be considered as groupings.

I am happy to refer to a much older post where I visually compared the size of the Voynich MS with a number of other more or less famous ones:
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