Musnad Abu Ya'la al-Mawsili 154:176

'Abd al-A'la narrated to us, Malik narrated to us, from Nafi', from 'Abd Allah ibn 'Umar, that a man asked the Messenger of Allah (may Allah bless him and grant him peace): "What should the *muhrim* (pilgrim in state of ihram) wear?" The Messenger of Allah (may Allah bless him and grant him peace) said: "He shall not wear the shirt, nor the turban, nor the trousers, nor the leather socks, unless one does not find a pair of sandals; then he may wear leather socks, and he should cut them below the ankles. And he shall not wear from the garments anything that has been touched by saffron or *wars* (a yellow dye)."