Photinus, of Gallograecia, a disciple of Marcellus, and ordained bishop of Sirmium, attempted to introduce the Ebionite heresy, and afterwards having been expelled from the church by the Emperor Valentinianus, wrote many volumes, among which the most distinguished are Against the nations, and To Valentinianus.
Source: De Viris Illustribus (Illustrious Men) (New Advent)