Musannaf Ibn Abi Shayba 35:419

Ibn Fudayl narrated to us, from ‘Ata’ ibn al-Sa’ib, from Sa’id ibn ‘Abd al-Rahman ibn Abza, from his father, who said: The Messenger of Allah (may Allah bless him and grant him peace) used to recite in the Witr: "Glorify the name of your Lord, the Most High," "Say, 'O disbelievers,'" and "Say, 'He is Allah, [who is] One.'"