Musannaf Ibn Abi Shayba 22:216

Abu Mu'awiyah narrated to us, from al-A'mash, from Shaqiq, from Masruq, from Abdullah ibn Amr, who said: The Messenger of Allah (may Allah bless him and grant him peace) said: "Take the Quran from four: from Abdullah ibn Mas'ud, Mu'adh ibn Jabal, Ubayy ibn Ka'b, and Salim, the freed slave of Abu Hudhayfah."