Sahih Muslim Book 20, Hadith Number 4473.

Chapter : The people are subservient to the Quraish and the Caliphate is the right of the Quraish.

It has been narrated on the authority of Abu Huraira that the Messenger of Allah (may peace be upon him) said: People are subservient to the Quraish: the Muslims among them being subservient to the Muslims among them, and the disbelievers among the people being subservient to the disbelievers among them.