Musannaf Ibn Abi Shayba 3:1882

Hushaym narrated to us, he said: Husayn and al-‘Awwam narrated to us, from Mujahid, from Ibn ‘Abbas, who said: He used to prostrate in [Surah] Sad. And he recited this verse: "Those are the ones whom Allah has guided, so from their guidance take an example."