Abu Anas says: Hadrat Uthman bin Affan (may Allah be pleased with him) performed ablution at al-Maqa'id and said: Shall I not show you the ablution of the Messenger of Allah (peace and blessings be upon him)? Then he performed ablution, washing each part three times. Sufyan says: Abu al-Nadr narrates from Abu Anas: Some Companions (may Allah be pleased with them) were with him, and he said: Did you not see the Messenger of Allah (peace and blessings be upon him) performing ablution like this? They said: Of course, we saw it just like this.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الطهارة / 371
(a) It is narrated from Sayyiduna Uthman bin Affan (may Allah be pleased with him) that he called for water, then performed ablution at al-Maqa'id, washing each part three times. Then he asked the Companions of the Messenger: Did you see the Messenger of Allah (peace and blessings be upon him) doing (ablution) like this? They said: Yes.
(b) The wording of al-Firyabi's hadith is: Sayyiduna Uthman (may Allah be pleased with him) performed ablution, washing each part three times, then said to the Companions of the Messenger: Is this how you saw the Messenger of Allah (peace and blessings be upon him)? They said: Yes.
(c) In the hadith of Abu Hudhayfah it is: he called for water at al-Maqa'id.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الطهارة / 372