Sunan At-Tirmidhi
Hadith #2223
Simak bin Harb narrated from Jabir bin Samurah who said "" The Messenger of Allah(s.a.w) said:'There will be twelve Amir after me.""' He said: ""Then he said something that I did not understand. So I asked the one who was next to me, who said that he(s.a.w) had said: 'All of them are from Quraish