Commercial Transactions (Kitab Al-Buyu)
Dawud :: Book 22 : Hadith 3377
Narrated AbuHurayrah:
The Apostle of Allah (peace_be_upon_him) having said: Allah, Most High, says: "I make a third with two partners as long as one of them does not cheat the other, but when he cheats him, I depart from them."