Abu Dawud Book 17, Hadith Number 3451.

Chapter : Not known.

Narated By AbuHurayrah : When AbuZur’ah made a business transaction with a man, he gave him the right of option. He then would tell him: Give me the right of option (to annul the bargain). He said: I heard AbuHurayrah say: The Apostle of Allah (PBUH) said: Two people must separate only by mutual consent.