Musnad Abu Ya'la al-Mawsili 150:268

'Uqbah narrated to us, Yunus narrated to us, Muhammad bin Ishaq narrated to us, from 'Abd al-Rahman bin al-Aswad, from his father, from 'Aishah, who said: When the Messenger of Allah (peace and blessings of Allah be upon him) would retire to his bed and intend to sleep while he was in a state of major ritual impurity (junub), before he performed ghusl, he would perform the wudu perfectly, then he would sleep.