Musnad Ahmad 907:156

Sufyan ibn 'Uyaynah narrated to us, from 'Abd al-Malik ibn 'Umayr, who said: I heard Jabir ibn Samurah al-Suwa'i saying: I heard the Messenger of Allah (peace and blessings of Allah be upon him) saying: "This matter will continue to proceed until twelve amirs (leaders) arise." Then he spoke a word that was hidden from me. I asked my father: "What did he say?" He said: "All of them are from Quraysh."