Sahih Muslim
The Book of Transactions (Kitab Al-Buyu)
Book Number: 010 / Hadith Number: 3692
Abu Huraira (Allah be pleased with him) reported Allah's Messenger (may peace be upon him) having given exemption of 'ariyya transactions measuring less than five wasqs or up to five wasqs (the narrator Dawud is in doubt whether it was five or less than five).