Musnad Ahmad 1153:2373

Hassan ibn Musa narrated to us, he said: Shayban narrated to us, from Yahya ibn Abi Kathir, from Abu Salamah, that Umar ibn Abd al-Aziz informed him that Urwah ibn al-Zubayr informed him that Aisha, the Mother of the Believers, informed him: "That the Messenger of Allah, may Allah bless him and grant him peace, used to kiss her while he was fasting."