Numbers 1:18

1:18 and they assembled the entire community together on the first day of the second month. Then the people recorded their ancestry by their clans and families, and the men who were twenty years old or older were listed by name individually,

Numbers 1:20

1:20 And they were as follows:

The descendants of Reuben, the firstborn son of Israel: According to the records of their clans and families, all the males twenty years old or older who could serve in the army were listed by name individually.

Numbers 1:22

1:22 From the descendants of Simeon: According to the records of their clans and families, all the males numbered of them twenty years old or older who could serve in the army were listed by name individually.

Numbers 1:32

1:32 From the sons of Joseph:

From the descendants of Ephraim: According to the records of their clans and families, all the males twenty years old or older who could serve in the army were listed by name.

Numbers 2:34

2:34 So the Israelites did according to all that the Lord commanded Moses; that is the way they camped under their standards, and that is the way they traveled, each with his clan and family.

Numbers 17:6

17:6 So Moses spoke to the Israelites, and each of their leaders gave him a staff, one for each leader, according to their tribes – twelve staffs; the staff of Aaron was among their staffs.