1. Fishbein M, Ajzen I (1975) Belief, attitude, intention and behavior: an introduction to theory and research. Addison-Wesley, Reading, MA
2. Osgood CE, Suci GJ, Tannenbaum PH (1957) The measurement of meaning. University of Illinois Press, Urbana, IL
3. Hofstätter PR (1972) Psychologie. Fischer, Frankfurt/Main
4. Hofstätter PR (1956) Farbsymbolik und Ambivalenz. Psychol Beitr 2:526–540
5. Haken H (1983) Advanced synergetics. Springer, Berlin