Musnad Abu Ya'la al-Mawsili 2:85

Abu Hammam al-Walid ibn Shuja' narrated to us, Abdullah ibn al-Mubarak narrated to us, from Hisham ibn Sa'd, from Zayd ibn Aslam, from his father, from Umar ibn al-Khattab, who said: "By Allah, were it not that we would leave the people of the end times with nothing, I would not have conquered a village for the people of Islam except that I would have divided it, just as the Messenger of Allah (may Allah bless him and grant him peace) divided Khaybar."