Musannaf Ibn Abi Shaybah

Hazrat Rubayyi’ bin Hirash (may Allah have mercy on him) narrates that Hazrat Hudhayfah (may Allah be pleased with him) said: We were sitting with the Noble Prophet (peace and blessings be upon him), and he (peace be upon him) said: Surely, I do not know how long I will remain among you. After me, you should follow these two, and he (peace be upon him) pointed towards Hazrat Abu Bakr (may Allah be pleased with him) and Hazrat Umar (may Allah be pleased with him).