These were the descendants of Judah by their clans: The Shelanite clan from Shelah, the Perezite clan from Perez, and the Zerahite clan from Zerah.
Jewish Publication Society of America Version (JPS1917) - Numbers 26:20 >And the sons of Judah after their families were: of Shelah, the family of the Shelanites; of Perez, the family of the Perezites; of Zerah, the family of the Zerahites.