The Book of Jubilees or the Little Genesis

"The Book of Jubilees, or, as it is sometimes called, 'the little Genesis,' purports to be a revelation given by God to Moses through the medium of an angel ('the angel of the Presence,' 1:27), and containing a history, divided up into jubilee-periods of forty-nine years, from the creation to the coming of Moses. Though the actual narrative of events is only carried down to the birth and early career of Moses, its author envisages the events of a later time, and in particular certain events of special interest at the time when he wrote, which was probably in the latter years of the second century B.C., perhaps in the reign of the Maccabean prince John Hyrcanus."

--from the Introduction