Jihad (Kitab Al-Jihad)
Dawud :: Book 14 : Hadith 2728
Narrated AbuUmrah (al-Ansari?):
We four persons, came to the Apostle of Allah (peace_be_upon_him), and we (i.e. each one of us) had horses. He therefore, allotted one portion for each of us, and two portions for his horse.