Book of Enoch (1 Enoch) 74:15
And in 5 years there are 1,770 days, so that for the moon the days in 8 years amount to 2,832 days.
Background and history of Book of Enoch (1 Enoch), and issues with this book.
R. H. Charles, The Book of Enoch (London: SPCK, 1917), public domain. The verse text is the English Wikisource transcription of that translation. Charles’s editorial signs are kept. He rearranges some verses in chapters 5, 39, 90, 91, and 106, so those chapters are not a straight 1, 2, 3 sequence.