Cita APA (7th ed.)

Gräf, G. (1968). Let's Speak English 3. Volk und Wissen.

Cita Chicago (17th ed.)

Gräf, Gerhard. Let's Speak English 3. Berlin: Volk und Wissen, 1968.

Cita MLA (8th ed.)

Gräf, Gerhard. Let's Speak English 3. Volk und Wissen, 1968.