Musnad Abu Ya'la al-Mawsili 110:148

Abu Khaythama narrated to us, Hushaym narrated to us, Yazid ibn Abi Ziyad narrated to us, from Mujahid, from Ibn Abbas, who said: The Prophet, peace and blessings of Allah be upon him, arrived performing Hajj, and he performed Tawaf and Sa'i, and he did not exit the state of Ihram because of the sacrificial animal (Hady). And he commanded those who did not have a sacrificial animal with them to perform Tawaf and Sa'i, and to shorten or shave their hair, and then to exit the state of Ihram.