Scofield Reference Notes (1917 Edition)Chapter 9
9:26 And he reigned over all the kings from the river even unto the land of the Philistines, and to the border of Egypt.
9:29 Now the rest of the acts of Solomon, first and last, are they not written in the book of Nathan the prophet, and in the prophecy of Ahijah the Shilonite, and in the visions of Iddo the seer against Jeroboam the son of Nebat?
"The river," i.e. Euphrates, to the border of Egypt, but not to the "river of Egypt." Cf. Genesis 15:18 yet to be fulfilled:
These books have perished. 1 Kings 11:29.