Musnad Ahmad 3:90

Abdullah ibn al-Walid narrated to us, Sufyan narrated to us, Salim Abu al-Nadr narrated to me, from Busr ibn Sa'id, from Uthman ibn Affan: That he called for water and performed ablution at the Maqa'id (seats/benches), and he performed ablution three times for each part. Then he said to the companions of the Messenger of Allah (peace and blessings of Allah be upon him): "Did you see the Messenger of Allah (peace and blessings of Allah be upon him) do this?" They said: "Yes." My father said: This al-Adani was in Makkah as the *mustamli* (dictation scribe) for Ibn Uyaynah.