Musnad Ahmad 1153:1190

Abu Abd al-Rahman narrated to us, Sa'id—meaning Ibn Abi Ayyub—narrated to us, 'Aqil narrated to me, from Ibn Shihab, from 'Urwah ibn al-Zubayr, from 'Aishah, who said: "When the Messenger of Allah (peace and blessings of Allah be upon him) wanted to sleep, he would join his hands together, then blow into them, then recite: 'Say, He is Allah, [who is] One,' 'Say, I seek refuge in the Lord of daybreak,' and 'Say, I seek refuge in the Lord of mankind.' Then he would wipe his face, his head, and the rest of his body with them." 'Aqil said: "And I saw Ibn Shihab doing that."