Cita APA (7th ed.)

Petzoldt, R. (1977). Ludwig van Beethoven. Bibliographisches Institut.

Cita Chicago (17th ed.)

Petzoldt, Richard. Ludwig Van Beethoven. Leipzig: Bibliographisches Institut, 1977.

Cita MLA (8th ed.)

Petzoldt, Richard. Ludwig Van Beethoven. Bibliographisches Institut, 1977.