Musnad Ahmad 27:530

'Abdullah ibn al-Harith narrated to us, Hanzalah narrated to me, from Nafi', from Ibn 'Umar, who said: Usamah came to him while he (the Prophet) was wearing it (a garment). The Messenger of Allah, peace and blessings of Allah be upon him, looked at him and said: "You clothed me." He said: "Tear it into head-coverings (khumur) for your wives, or fulfill your need with it."