Musannaf Ibn Abi Shayba 38:9

'Abbad ibn al-'Awwam narrated to us, from al-Salt ibn Bahram, from 'Abd al-Malik ibn Sil', from 'Abd Khayr: That 'Ali did not take captives on the Day of the Camel, and he did not take a fifth (khums). They said, "O Commander of the Faithful, will you not take a fifth of their wealth?" He said, "This is 'A'isha; shall I take her as a captive?" They said, "It is nothing but this, it is nothing but this."