ROSENTHAL, Harold; WARRACK, John. The concise Oxford dictionary of opera. London: Oxford University Press, 1985. Dostupné online. ISBN0-19-311321-X. S. 103.
ROSENTHAL, Harold; WARRACK, John. The concise Oxford dictionary of opera. London: Oxford University Press, 1985. Dostupné online. ISBN0-19-311321-X.