Musnad Ahmad 26:356

'Affan narrated to us, 'Abd al-Wahid narrated to us, Sulayman al-A'mash narrated to us, from Shaqiq ibn Salamah, who said: 'Abdullah ibn Mas'ud delivered a sermon to us and said: "I have taken from the mouth of the Messenger of Allah, may Allah bless him and grant him peace, seventy-odd surahs." And Zayd ibn Thabit was a boy with two braids, playing with the boys.