Warbin, R. W., Altman, H., Gynther, M. D., & Sletten, I. W. (1972). A new empirical automated MMPI interpretive program: 2-8 and 8-2 code types. Journal of Personality Assessment, 36(6), 581–584. http://www.erlbaum.com/Journals/journals/JPA/jpa.htm