Book of Enoch (1 Enoch) 71:7
And round about were Seraphin, Cherubin, and Ophannin: And these are they who sleep not And guard the throne of His glory.
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.