Musannaf Ibn Abi Shayba 33:743

Waki’ narrated to us, from al-‘Ala’ ibn ‘Abd al-Karim, that he heard it from Ibn Sabit regarding: "And indeed, it is in the Mother of the Book with Us, exalted and full of wisdom." He said: "In the Mother of the Book is everything that will come to pass until the Day of Resurrection."