Musannaf Ibn Abi Shayba 3:510

Ibn ‘Uyaynah narrated to us, from al-Zuhri, from ‘Ubayd Allah, from Ibn ‘Abbas, who said: I came, and al-Fadl, upon a female donkey, while the Prophet (may Allah bless him and grant him peace) was leading the people in prayer at ‘Arafah. We passed by a part of the row, then we dismounted and left it to graze, and he did not say anything to us.