Cita APA (7th ed.)

Wolff, H. C. (1971). Die Oper. Volk.

Cita Chicago (17th ed.)

Wolff, Hellmuth Christian. Die Oper. Köln: Volk, 1971.

Cita MLA (8th ed.)

Wolff, Hellmuth Christian. Die Oper. Volk, 1971.