M. Pierpaoli, Il libro di Agnello Istorico. Le vicende di Ravenna antica fra storia e realtà, Ravenna 1988.
The Venetians are mentioned twice in the biography of Sergius, archbishop of Ravenna (744–769, in the “Liber pontificalis ecclesiae Ravennatis”.
The eventful reign of John VI, bishop of Ravenna (726–744), from the “Liber pontificalis ecclesiae Ravennatis”.