Musnad Ahmad 1153:422

Musa ibn Dawud and al-Ashyab narrated to us, they said: Ibn Lahi'ah narrated to us, and Ishaq ibn 'Isa said: Ibn Lahi'ah narrated to me. Al-Ashyab said: Khalid ibn Abi 'Imran narrated to us, from al-Qasim, from 'Aishah: "That the Messenger of Allah (peace and blessings of Allah be upon him) used to place his head in her lap while she was menstruating, and he would recite the Qur'an."