Musnad Ahmad 1159:24

'Abd al-Malik ibn 'Amr narrated to us, he said: 'Ali—meaning Ibn al-Mubarak—narrated to us, from Yahya, from Abu Salamah, from Abu Sufyan ibn Sa'id ibn al-Akhnas, who said: I entered upon Umm Habibah, and she called for *sawiq* (roasted barley/wheat flour) for me, so I drank it. She then said: "Will you not perform ablution?" I said: "I have not broken my ablution." She said: "Indeed, the Messenger of Allah (peace and blessings of Allah be upon him) said: 'Perform ablution from what fire has touched.'"