1. From op.99 Collection: Concert Programs (SOM) Contributers: Schumann, Robert (composer) and John O'Halla (piano) Performance: Performance Performance Date: 1969-12-18 Location: Music and Performing Arts Library, University of Illinois Concert Program: vol. 18, p. 329
2. Thirty-two Variations in C minor Collection: Concert Programs (SOM) Contributers: Beethoven, Ludwig van (composer) and John O'Halla (piano) Performance: Performance Performance Date: 1969-12-18 Location: Music and Performing Arts Library, University of Illinois Concert Program: vol. 18, p. 329