Musnad Ahmad 1153:125

Sufyan narrated to us, saying: "I saw the glistening of the perfume," and it was read to Sufyan: I heard 'Ata' ibn al-Sa'ib, from Ibrahim, from al-Aswad, from 'Aisha: "In the parting of the hair of the Messenger of Allah, may Allah bless him and grant him peace, after three [days/nights]."