[en] [Gutenberg 35128] • Wagner : The Story of the Boy Who Wrote Little Plays Independently Published
[en] [Gutenberg 1487] • The Perfect Wagnerite: A Commentary on the Niblung's Ring Dover Publications
[en] [Gutenberg 42875] • Wagner as I Knew Him University Press of the Pacific
[en] [Gutenberg 31526] • Life of Wagner / Biographies of Musicians Palala Press
[en] [Gutenberg 52166] • The Case of Wagner / Complete Works, Volume 8 Scholar's Choice
[en] [Gutenberg 7834] • Wagner's "Tristan und Isolde": An Essay on the Wagnerian Drama Public Domain Books
[en] [Gutenberg 54426] • Modern Musical Drift Potter Press