1. Ethical principles of psychologists;American Psychologist,1990
2. The external validity of experiments;Bracht;American Educational Research Journal,1968
3. Experiment und Feldexperiment [Experiment and field experiment];Bredenkamp,1969
4. Theorie und Planung psychologischer Experimente [Theory of Psychological Experiments and their Planning];Bredenkamp,1980
5. Verfahren zur Ermittlung des Typ der statistischen Wechselwirkung [Procedures for the identification of detecting the type of statistical interaction];Bredenkamp;Psychologische Beiträge,1982