Musnad Ahmad 1153:1142

'Abd al-Rahman narrated to us, from Mu'awiyah, from 'Abd Allah ibn Abi Qays, who said: I asked 'Aishah: "How was the sleep of the Messenger of Allah (peace and blessings of Allah be upon him) when in a state of major ritual impurity (janabah)? Would he perform ghusl before he slept?" She said: "He used to do all of that. Sometimes he would perform ghusl, then sleep, and sometimes he would perform wudu, then sleep." He said: I said to her: "How was the recitation of the Messenger of Allah (peace and blessings of Allah be upon him) at night? Would he recite aloud or silently?" She said: "He used to do all of that. Sometimes he would recite aloud, and sometimes he would recite silently."