Exodus 6:13-17

Nevertheless, the Lord spoke to Moses and to Aaron and gave them a command concerning the sons of Israel and Pharaoh king of Egypt, to bring the sons of Israel out of the land of Egypt. The Heads of Israel

These are the heads of their fathers’ households. The sons of Reuben, Israel’s firstborn: Hanoch and Pallu, Hezron and Carmi; these are the families of Reuben.

And the sons of Simeon: Jemuel, Jamin, Ohad, Jachin, Zohar, and Shaul the son of a Canaanite woman; these are the families of Simeon.

And these are the names of the sons of Levi according to their generations: Gershon, Kohath, and Merari; and the length of Levi’s life was 137 years.

The sons of Gershon: Libni and Shimei, according to their families.