The Book of Cynog (Medieval Latin: Liber Knauc; Middle Welsh: Llyfr Kynawc; Welsh: Llyfr Cynog) was a text of medieval Welsh law.
[1] It is quoted extensively by surviving sources but does not appear to have survived intact.
However, the first 75 folios of Peniarth MS. 35 seem to be a medieval attempt to reconstruct the earlier book.
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