The sons of Levi: Gershon, Kohath, and Merari.
1 Chronicles 6:1
But Aaron and his sons made offerings on the altar of burned offering, and on the altar of perfume, for all the work of the most holy place, and to take away the sin of Israel, doing everything ordered by Moses, the servant of God.
1 Chronicles 6:49
And the towns which you give the Levites are to be the six safe places to which the taker of life may go in flight; and in addition you are to give them forty-two towns.
Take the Levites out from among the children of Israel and make them clean.