Numbers 3:16-20

So Moses counted them according to the word of the Lord, just as he had been commanded.

These, then, are the sons of Levi by their names: Gershon, Kohath, and Merari.

And these are the names of the sons of Gershon by their families: Libni and Shimei;

and the sons of Kohath by their families: Amram and Izhar, Hebron and Uzziel;

and the sons of Merari by their families: Mahli and Mushi. These are the families of the Levites according to their fathers’ households.