Musannaf Ibn Abi Shayba 27:140

Muhammad ibn Fudayl narrated to us, from ‘Ata’, from Sa‘id ibn Jubayr, from Ibn ‘Abbas, who said: Musa asked his Lord a request, and Musa chose seventy men from his people, until he reached what was written for them in the Torah and the Gospel. Then it was given to Muhammad, may Allah bless him and grant him peace.