↑ Altrichter, H., & Gstettner, P. (1993). Action research: a closed chapter in the history of German social science?. Educational Action Research 1 (3), 329–360.
↑ In an empirical study by Haggbloom et al. using six criteria such as citations and recognition, Lewin was found to be the 18th-most eminent psychologist of the 20th century. Haggbloom, S.J. et al. (2002). The 100 Most Eminent Psychologists of the 20th Century. Review of General Psychology. Vol. 6, No. 2, 139–152. Haggbloom et al. combined three quantitative variables: citations in professional journals, citations in textbooks, and nominations in a survey given to members of the Association for Psychological Science, with three qualitative variables (converted to quantitative scores): National Academy of Science (NAS) membership, American Psychological Association (APA) President and/or recipient of the APA Distinguished Scientific Contributions Award, and surname used as an eponym. Then the list was rank ordered.
