Musannaf Ibn Abi Shayba 9:910

Abu Bakr narrated to us, he said: Jarir narrated to us, from Mansur, from Ibrahim, from al-Aswad, from Aisha, she said: When one of us was menstruating, the Prophet (peace and blessings of Allah be upon him) would order her to wrap an izar (waist-wrapper) around herself, then he would have intimate contact with her.