Musnad Ahmad 27:1926

'Abd al-Razzaq narrated to us, Ma'mar narrated to us, from Ayyub, from Nafi', from Ibn 'Umar, who said: "We were in a military expedition, and our shares reached eleven camels for every man. Then, the Messenger of Allah, peace and blessings of Allah be upon him, gave us an additional camel each as a reward (nafal) after that."