Musnad Imam Shafi'i

Yahya al-Mazini (may Allah have mercy on him) said to Abdullah bin Zayd al-Ansari (may Allah be pleased with him): "Can you show me how the Messenger of Allah (ﷺ) performed ablution?" Abdullah bin Zayd (may Allah be pleased with him) replied: "Yes," then he called for water for ablution, poured it on his hands and washed his hands twice, rinsed his mouth and put water into his nose three times, then washed his face three times, then washed his hands up to and including the elbows twice, then wiped his head with both hands, moving his hands from the front to the back and then from the back to the front. He started from the beginning of the head, then took both hands to the nape, then brought them back to where he had started while wiping, then washed both his feet.

It is narrated from Abdullah bin Zaid (may Allah be pleased with him) that when the Messenger of Allah (ﷺ) performed ablution, he washed his face three times, and washed his hands twice each, and wiped his head with his hands such that he moved both hands from the front of the head to the back, and then brought them from the back to the front. He started from the front part of the head and took his hands to the nape, and then in the same way brought both hands back to the place from where he had started wiping. Then he washed both his feet.