Strabo Geography 7.3.12

[12] But there is also another division of the country which has endured from early times, for some of the people are called Daci, whereas others are called Getae—Getae, those who incline towards the Pontus and the east, and Daci, those who incline in the opposite direction towards Germany and the sources of the Ister. The Daci, I think, were called Daï in early times; whence the slave names “Geta” and “Daüs” ¹ which prevailed among the Attic people; for this is more probable than that “Daüs” is from those Scythians who are called “Daae,” ² for they live far away in the neighborhood of Hyrcania, and it is not reasonable to suppose that slaves were brought into Attica from there; for the Attic people were wont either to call their slaves by the same names as those of the nations from which they were brought (as “Lydus” or “Syrus ”), or addressed them by names that were prevalent in their countries (as “Manes”or else “Midas” for the Phrygian, or “Tibius” for the Paphlagonian). But though the tribe was raised to such a height by Boerebistas, it has been completely humbled by its own seditions and by the Romans; nevertheless, they are capable, even today, of sending forth an army of forty thousand men.