Musannaf Ibn Abi Shayba 3:5431

Ibn ‘Uyaynah narrated to us, from Yazid, from Ibn Abi Layla, who said: I reached the people while they were numerous (or complete), and no one informed me that he prayed the Duha prayer except Umm Hani, who informed me that he prayed it as eight rak'ahs.