Musnad Ahmad 32:1564

Hassan narrated to us, Hammad ibn Salamah narrated to us, from Thabit al-Bunani, from Anas ibn Malik, who said: "When the Messenger of Allah (peace and blessings of Allah be upon him) wanted the cupper to shave his head, Abu Talha took the hair of one side of his head with his hand, and he took his hair and brought it to Umm Sulaym." He said: "And Umm Sulaym used to mix it into her perfume."