Greffrath, M. (1988). Robert Jungk / Mathias Greffrath; Diethart Kerbs. -. Edition Echolot.
Cita Chicago (17th ed.)Greffrath, Mathias. Robert Jungk / Mathias Greffrath; Diethart Kerbs. -. Berlin: Edition Echolot, 1988.
Cita MLA (8th ed.)Greffrath, Mathias. Robert Jungk / Mathias Greffrath; Diethart Kerbs. -. Edition Echolot, 1988.
Atenció: Aquestes cites poden no estar 100% correctes.