Book of Jubilees 4:15
And in the second week of the tenth jubilee [449-55 A.M.] Mahalalel took unto him to wife DinaH, the daughter of Barakiel the daughter of his father's brother, and she bare him a son in the third week in the sixth year, [461 A.M.] and he called his name Jared, for in his days the angels of the Lord descended on the earth, those who are named the Watchers, that they should instruct the children of men, and that they should do judgment and uprightness on the earth.
Background and history of Book of Jubilees, and issues with this book.
R. H. Charles, The Book of Jubilees, in The Apocrypha and Pseudepigrapha of the Old Testament, vol. 2 (Oxford: Clarendon Press, 1913). Public domain in the United States (published 1913). Charles died in 1931, so the book is in the public domain in the United Kingdom. The verse text is the Joshua Williams transcription at pseudepigrapha.com. Jubilees 1:8 and 1:9 are divided at the break in the 1902 Clarendon scan (archive.org bookofjubileesor00char), where verse 9 begins “For they will forget.” That scan also numbers the angel-of-the-presence sentence as 1:29. Editorial brackets in the translation are Charles’s.