Musnad Ahmad 26:783

'Affan narrated to us, Abu 'Awanah narrated to us, from Firas, from 'Amir, from Masruq, from 'Abdullah, who said: "He would sometimes narrate to us from the Messenger of Allah, may Allah bless him and grant him peace, and he would stumble, and his color would change, and he would say: 'Like this, or close to this.'"