LXX Num 4:27

κατὰ στόμα Ἀαρὼν καὶ τῶν υἱῶν αὐτοῦ ἔσται ἡ λειτουργία τῶν υἱῶν Γεδσὼν κατὰ πάσας τὰς λειτουργίας αὐτῶν καὶ κατὰ πάντα τὰ ἔργα δι’ αὐτῶν· καὶ ἐπισκέψῃ αὐτοὺς ἐξ ὀνομάτων πάντα τὰ ἄρτα ὑπ’ αὐτῶν.

All the service of the Gershonites—all their transport duties and other work—is to be done at the direction of Aaron and his sons; you are to assign to them all that they are responsible to carry.