Sahih Bukhari
Good Manners and Form (Al-Adab)
Volume: 008 / Book Number: 073 / Hadith Number: 106
Narrated 'Asim:
I said to Anas bin Malik, "Did it reach you that the Prophet said, "There is no treaty of brotherhood in Islam'?" Anas said, "The Prophet made a treaty (of brotherhood) between the Ansar and the Quraish in my home."