Musnad Ahmad 3:127

'Abdullah narrated to us, 'Uthman ibn Abi Shaybah narrated to me, Yunus ibn Abi al-Ya'fur al-'Abdi narrated to us, from his father, from Muslim Abu Sa'id, the freed slave of 'Uthman ibn 'Affan: That 'Uthman ibn 'Affan freed twenty slaves, and he called for trousers and tied them upon himself, and he had not worn them in the Pre-Islamic period nor in Islam. He said: "I saw the Messenger of Allah, peace and blessings of Allah be upon him, last night in a dream, and I saw Abu Bakr and 'Umar, and they said to me: 'Be patient, for you will break your fast with us tomorrow night.'" Then he called for a copy of the Mushaf and spread it out before him, and he was killed while it was between his hands.