Musnad Abu Ya'la al-Mawsili 209:71

Mujahid ibn Musa al-Khutali narrated to us, Abu Mu'awiyah narrated to us, Musa ibn Ubaydah al-Rabadhi narrated to us, from Sa'id ibn Abi Ayyash al-Zuraqi, from Anas ibn Malik, from Umm Salamah, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "I saw what my Ummah will do after me, so I chose intercession for them on the Day of Resurrection."