Musnad Ahmad 5:482

Abdullah narrated to us, Khalaf ibn Hisham al-Bazzar narrated to us, Abu al-Ahwas narrated to us, from Abu Ishaq, from Abu Hayyah, who said: I saw Ali performing ablution. He washed his palms until he had cleansed them, then he rinsed his mouth three times, then he inhaled water into his nose three times, and he washed his face three times, and his forearms three times, and he wiped his head, and he washed his feet up to the ankles. Then he took the remainder of his ablution water and drank it while he was standing. Then he said: "I wanted to show you how the ablution of the Messenger of Allah, may Allah bless him and grant him peace, was."