Musnad Abu Ya'la al-Mawsili 153:101

Muhammad ibn Abdullah ibn Numayr narrated to us, Ishaq ibn Sulayman al-Razi narrated to us, Hanzalah narrated to us, he said: I heard Salim, he said: I heard Ibn Umar saying: Usamah went out wearing a *hullah* (a two-piece garment). The Messenger of Allah, peace and blessings of Allah be upon him, said: "Tear it into head-coverings (*khumur*) for your womenfolk."