Book of Enoch (1 Enoch) 74:10
And if five years are added together the sun has an overplus of thirty days, and all the days which accrue to it for one of those five years, when they are full, amount to 364 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.