Genesis 25:18-20

Young's Literal Translation

¹⁸ and they tabernacle from Havilah unto Shur, which [is] before Egypt, in [thy] going towards Asshur; in the presence of all his brethren hath he fallen.

¹⁹ And these [are] births of Isaac, Abraham's son: Abraham hath begotten Isaac;

²⁰ and Isaac is a son of forty years in his taking Rebekah, daughter of Bethuel the Aramaean, from Padan-Aram, sister of Laban the Aramaean, to him for a wife.