Musnad Ahmad 1153:949

'Abd al-Wahhab narrated to us, he said: Hisham informed us, from Hammad, from Ibrahim, from al-Aswad ibn Yazid, from 'Aisha, that she said: "It is as if I am looking at the glistening of the perfume in the parting of the hair of the Messenger of Allah, may Allah bless him and grant him peace, while he was in the state of ihram."