Library Diodorus Siculus Library of History
Book II
Chapter 28: Arbaces as king
[8] So the empire of the Assyrians, which had endured from the time of Ninus through thirty generations, for more than one thousand three hundred years, was destroyed by the Medes in the manner described above.
Book I: English by G. Booth (1814), via Wikisource. Book II: English by C. H. Oldfather, Loeb Classical Library (1933), via LacusCurtius. Public domain.