Cita APA (7th ed.)

Specht, J. (1976). Perpetuum mobile. Verlag der Nation.

Cita Chicago (17th ed.)

Specht, Joachim. Perpetuum Mobile. Berlin: Verlag der Nation, 1976.

Cita MLA (8th ed.)

Specht, Joachim. Perpetuum Mobile. Verlag der Nation, 1976.