Book 12
3.3
Now as for the Bithynians, it is agreed by most writers that, though formerly Mysians, they received this new name from the Thracians—the Thracian Bithynians and Thynians—who settled the country in question, and they put down as evidences of the tribe of the Bithynians that in Thrace certain people are to this day called Bithynians, and of that of the Thynian, that the coast near Apollonia and Salmydessus is called Thynias. And the Bebryces, who took up their abode in Mysia before these people, were also Thracians, as I suppose. It is stated that even the Mysians themselves are colonists of those Thracians who are now called Moesians.See 7. 3. 2. Such is the account given of these people.