Musnad Abu Ya'la al-Mawsili 150:88

Abu Ma'mar Isma'il ibn Ibrahim narrated to us, Hakim ibn Nafi' narrated to us, from Hisham ibn 'Urwah, from his father, from 'Aishah, who said: The Messenger of Allah (may Allah bless him and grant him peace) said: "The two prostrations of forgetfulness suffice in the prayer for every addition and omission."