Musannaf Ibn Abi Shayba 20:12

Abu Bakr narrated to us, he said: Zayd ibn al-Hubab narrated to us, he said: Sayf ibn Sulayman al-Makki narrated to us, he said: Qays ibn Sa'd informed me, from 'Amr ibn Dinar, from Ibn 'Abbas, that the Messenger of Allah (may Allah bless him and grant him peace) judged by an oath and a witness.