Perison, Harry. “The Quarter-Tone System of Charles Ives”. Current Musicology, no. 18 (January 3, 2020): 96–104. Accessed December 30, 2025. https://journals.library.columbia.edu/index.php/lawandarts/%252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252509https:/journals.library.columbia.edu/index.php/currentmusicology/article/view/4370.