Abu Dawud
Purification (Kitab Al-Taharah)
Book Number: 001 / Hadith Number: 128
Narated By Al-Rubayyi' daughter of Mu'awwidh b. 'Afra' : The Messenger of Allah (pbuh) performed ablution in her presence. He wiped the whole of his head from its upper to the lower part moving every side. He did not move the hair from their original position.