Numbers 4:37-39

New International Version - UK

³⁷ This was the total of all those in the Kohathite clans who served at the tent of meeting. Moses and Aaron counted them according to the Lord’s command through Moses.

³⁸ The Gershonites were counted by their clans and families. ³⁹ All the men from thirty to fifty years of age who came to serve in the work at the tent of meeting,