Musnad Ahmad 1153:666

Muhammad ibn Ja‘far narrated to us, he said: Shu‘bah narrated to us, from Hisham ibn ‘Urwah, from his father, from ‘Aishah, from the Prophet, peace and blessings of Allah be upon him: "That he was in I‘tikaf in the mosque, and ‘Aishah would come, and he would put his head out, and she would comb his hair while she was menstruating."