Musnad Ahmad 5:379

Ishaq ibn Yusuf narrated to us, from Sharik, from al-Suddi, from Abd Khayr, who said: I saw Ali call for water to perform ablution. He wiped with it, a wiping, and he wiped over the tops of his feet. Then he said: "This is the ablution of one who has not broken his state of purity." Then he said: "Had I not seen the Messenger of Allah, peace and blessings of Allah be upon him, wipe over the tops of his feet, I would have thought that their soles were more deserving." Then he drank the remainder of his ablution water while standing. Then he said: "Where are those who claim that it is not appropriate for anyone to drink while standing?"