Sahih Muslim , Book 20, Hadith 4480 (USC-MSA) ⓘ

It has been narrated on the authority of Jabir b. Samura who said: I heard the Messenger of Allah say: Islam will continue to be triumphant until there have been twelve Caliphs. Then the Prophet said something which I could not understand. I asked my father: What did he say? He said: He has said that all of them (twelve Caliphs) will be from the Quraish.

حَدَّثَنَا هَدَّابُ بْنُ خَالِدٍ الأَزْدِيُّ، حَدَّثَنَا حَمَّادُ بْنُ سَلَمَةَ، عَنْ سِمَاكِ بْنِ حَرْبٍ، قَالَ سَمِعْتُ جَابِرَ بْنَ سَمُرَةَ، يَقُولُ سَمِعْتُ رَسُولَ اللَّهِ صلى الله عليه وسلم يَقُولُ ‏"‏ لاَ يَزَالُ الإِسْلاَمُ عَزِيزًا إِلَى اثْنَىْ عَشَرَ خَلِيفَةً ‏"‏ ‏.‏ ثُمَّ قَالَ كَلِمَةً لَمْ أَفْهَمْهَا فَقُلْتُ لأَبِي مَا قَالَ فَقَالَ ‏"‏ كُلُّهُمْ مِنْ قُرَيْشٍ ‏"‏ ‏.‏