Virdung's Keyboard Illustrations , 1962
Materiale a stampa,
spoglio
PER 85
The Galpin Society Journal, XV, Marzo, 82-88
The "Chord" in Monocord, Clavicord, Harpsicord and Vocal Cord , 1955
Materiale a stampa,
spoglio
PER 85
The Galpin Society Journal, VIII, Marzo, 47-49