Setton, Kenneth (1976—1984), The Papacy and the Levant, 1204-1571, four volumes, American Philosophical Society, p. 73, ISBN978-0-87169-114-9, »...... The spurious correspondence of July and August 1443, between Ladislas and Scanderbeg (made up by Barletius, who should assigned it to the year 1444) ......... He also invented a correspondence between Skanderbeg and Sultan Mehmed II to fit his interpretations of the events in 1461—1463 ...«