Ditfurth, J. (1995). Was ich denke / Jutta Ditfurth. -. Goldmann Verlag.
Cita Chicago (17th ed.)Ditfurth, Jutta. Was Ich Denke / Jutta Ditfurth. -. München: Goldmann Verlag, 1995.
Cita MLA (8th ed.)Ditfurth, Jutta. Was Ich Denke / Jutta Ditfurth. -. Goldmann Verlag, 1995.
Atenció: Aquestes cites poden no estar 100% correctes.