Musannaf Ibn Abi Shayba 38:183

Yazid ibn Harun narrated to us, [saying] al-Awwam ibn Hawshab informed us, from al-Shaybani, from Usayr ibn Amr, from Sahl ibn Hunayf, from the Prophet, peace and blessings of Allah be upon him, who said: "A people will emerge from the direction of the East, with their heads shaved."