Musnad Ahmad 3:96

Sufyan ibn 'Uyaynah narrated to us, from Ayyub ibn Musa, from Nabih ibn Wahb, who said: 'Umar ibn 'Ubayd Allah ibn Ma'mar complained of his eyes, so he sent to Aban ibn 'Uthman—Sufyan said: And he was the governor—asking what he should do with them. He said: He said, "Apply *sabir* (aloe) to them as a compress, for I heard 'Uthman narrating that from the Messenger of Allah, may Allah bless him and grant him peace."