Musnad Abu Ya'la al-Mawsili 150:417

Muhammad ibn Bakkar narrated to us, Abu Ma'shar narrated to us, Hisham ibn 'Urwah narrated to me, from his father, from 'Aishah, that the Messenger of Allah (may Allah bless him and grant him peace) made the waiting period ('iddah) of Barirah, when her husband separated from her, the waiting period of a divorced woman.