Musnad Abu Ya'la al-Mawsili 110:179

Isma'il ibn Musa narrated to us, Husayn ibn 'Isa narrated to us, from Ma'mar, from al-Zuhri, from Abu Hazim, from Ibn 'Abbas, who said: While the Messenger of Allah (peace and blessings of Allah be upon him) was at al-Hudaybiyyah, he said: "Allah is the Greatest, Allah is the Greatest. The victory of Allah and the conquest have come, and the people of Yemen have come." It was said: "O Messenger of Allah, and who are the people of Yemen?" He said: "A people whose hearts are tender and whose natures are soft. Faith is Yemeni, jurisprudence is Yemeni, and wisdom is Yemeni."