References
- KREUTZER, J. S., SCHEPANK, H. Heredity andenvironmental factors in neuroses: Depth psychology studies 50 pairs of twins.. Monographien aus dem Gesamtgebiete der Psychiatrie, 1974.
- HERRMANN, D PARENTEN, R. Retraining Cognition: Techniques and Application (Maryland:Aspen Publishers),1996.