Yahya related to me from Malik from Zayd ibn Aslam from al-Qaqaibn Hakim that Abu Yunus, the mawla of A'isha, umm al-muminin said,''A'isha ordered me to write out a Qur'an for her. She said, 'Whenyou reach this ayat, let me know, "Guard the prayers carefully and themiddle prayer and stand obedient to Allah." ' When I reached it I toldher, and she dictated to me, 'Guard the prayers carefully and themiddle prayer and the asr prayer and stand obedient to Allah.' A'ishasaid, 'I heard it from the Messenger of Allah, may Allah bless him andgrant him peace.' "
App reference: Book 8, Hadith 26
USC-MSA web (English) reference: Book 8, Hadith 26
Arabic reference: Book 8, Hadith 315