It is narrated from Sayyidah Rubayyi' bint Mu'awwidh (may Allah be pleased with her) that the Messenger of Allah (peace and blessings be upon him) performed ablution in her presence, and he wiped his head. He wiped the whole head over the hair, every part in the direction in which the hair grows, and he did not move the hair from its position.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الطهارة / 275