W. F. Apthorp: The Opera Past and Present (New York, 1901).

M. A. de Bovet: Charles Gounod, his Life and Works, Eng. transl. (London, 1891).

An Englishman in Paris (Notes and Recollections) (New York).

André Lebon: Modern France (New York, 1907).

R. A. Streatfeild: Modern Music and Musicians (London, 1906).

R. A. Streatfeild: The Opera (London, 1897).

In German

Oskar Bie: Die Oper (Berlin, 1913).

Max Chop: Führer durch die Opernmusik (Berlin, 1912).

H. Heine: Musikalische Berichte aus Paris (Hamburg, 1890).