Statistics for occurrence #1 of “Euphrates” in book 1, section 220 of Flavius Josephus, Antiquities of the Jews:
...rived originally. Of this wife were
born to Ismael twelve sons; Nabaioth, Kedar, Abdeel, Mabsam, Idumas, Masmaos,
Masaos, Chodad, Theman, Jetur, Naphesus, Cadmas. These inhabited all the
country from Euphrates to the Red Sea, and called it Nabatene. They are
an Arabian nation, and name their tribes from these, both because of their
own virtue, and because of the dignity of Abraham their father.
...