Exodus 6:16-19

And these are the names of the sons of Levi according to their generations; Gershon, and Kohath, and Merari: and the years of the life of Levi were an hundred thirty and seven years. The sons of Gershon; Libni, and Shimi, according to their families. And the sons of Kohath; Amram, and Izhar, and Hebron, and Uzziel: and the years of the life of Kohath were an hundred thirty and three years. And the sons of Merari; Mahali and Mushi: these are the families of Levi according to their generations.