Hughes, Philip.Chapter V: 'Facilis Descensus ...' 1471–1517: A Papacy of Princes // History of the Church: Volume 3: The Revolt Against the Church: Aquinas to Luther (англ.). — revised. — London: Sheed & Ward[англ.], 1979. — P. 415. — ISBN 978-0-7220-7983-6.
Ullmann, Walter.Julius and the Schismatic Cardinals // Schism, Heresy and Religious Protest: Papers Read at the Tenth Summer Meeting and the Eleventh Winter Meeting of the Ecclesiastical History Society (англ.) / Baker, Derek. — Cambridge, England: Ecclesiastical History Society by Cambridge University Press, 1972. — P. 177—178. — ISBN 978-0-521-08486-4.
Hughes, Philip.Chapter V: 'Facilis Descensus ...' 1471–1517: A Papacy of Princes // History of the Church: Volume 3: The Revolt Against the Church: Aquinas to Luther (англ.). — revised. — London: Sheed & Ward[англ.], 1979. — P. 415. — ISBN 978-0-7220-7983-6.