Encyclopedia Dantesca, Biblioteca Treccani, 2005, vol. 7, article Contrapasso.
Mark Musa, commentary notes in The Divine Comedy. Volume 1: Inferno. Penguin Classics: 1984, pp. 37-38.
Mark Musa, commentary notes in The Divine Comedy. Volume 1: Inferno. Penguin Classics: 1984, pp. 37-38.
Inferno, Canto XX, lines 14–15, Mandelbaum translation.
Dorothy L. Sayers, Hell, notes on Canto XX. /wiki/Dorothy_L._Sayers
Peter Brand and Lino Pertile, The Cambridge History of Italian Literature, 2nd ed, Cambridge University Press, 1999, ISBN 0-521-66622-8, pp. 63-64. https://books.google.com/books?id=3uq0bObScHMC&pg=PA63
"Princeton Dante Project (2.0)". Etcweb.princeton.edu. Archived from the original on 2019-04-29. Retrieved 2013-08-09. https://web.archive.org/web/20190429113047/http://etcweb.princeton.edu/dante/pdp/
"Dante; Poetry of Dante Alighieri; full text of Dante's Divine Comedy - Inferno, Purgatorio, Paradiso, at". Everypoet.com. Archived from the original on 2011-09-01. Retrieved 2013-08-09. https://web.archive.org/web/20110901224137/http://www.everypoet.com/archive/poetry/dante/dante_contents.htm
Dante Alighieri (1971). Inferno. Charles S. Singleton. London: Routledge and K. Paul. ISBN 0-7100-6996-0. OCLC 2656376. 0-7100-6996-0
Mark Musa, commentary notes in The Divine Comedy. Volume 1: Inferno. Indiana University Press, 1996, ISBN 0-253-32968-X, p. 380. /wiki/ISBN_(identifier)
Mark Musa, commentary notes in The Divine Comedy. Volume 1: Inferno. Indiana University Press, 1996, ISBN 0-253-32968-X, p. 380. /wiki/ISBN_(identifier)
Encyclopedia Dantesca, Biblioteca Treccani, 2005, vol. 7, article Contrapasso.