Musannaf Ibn Abi Shaybah 32532 — Reports from Uthman

It is narrated from Sayyiduna Ibn Umar (may Allah be pleased with them both) that Sayyiduna Uthman (may Allah be pleased with him) was relating this to the people in the morning: "Last night I saw the Messenger of Allah (peace and blessings be upon him) in a dream, and he said: 'O Uthman! Break your fast with us.'" He fasted, and he was martyred that same day.