Tosefta for I Chronicles 24:17

לְיָכִין֙ אֶחָ֣ד וְעֶשְׂרִ֔ים לְגָמ֖וּל שְׁנַ֥יִם וְעֶשְׂרִֽים׃

the one and twentieth to Jachin, the two and twentieth to Gamul;