Cross reference
Judges 11:22
22 and they possess all the border of the Amorite from Arnon, and unto the Jabbok, and from the wilderness, and unto the Jordan.
Deuteronomy 2:36
36 `From Aroer, which `is' by the edge of the brook Arnon, and the city which `is' by the brook, even unto Gilead there hath not been a city which `is' too high for us; the whole hath Jehovah our God given before us.