Apel, W. (1947). Masters of the keyboard: A brief survey of pianoforte music. Harvard University.
Cita Chicago (17th ed.)Apel, Willi. Masters of the Keyboard: A Brief Survey of Pianoforte Music. Cambridge: Harvard University, 1947.
Cita MLA (9th ed.)Apel, Willi. Masters of the Keyboard: A Brief Survey of Pianoforte Music. Harvard University, 1947.
Atenció: Aquestes cites poden no estar 100% correctes.