“The Exploratory and Confirmatory Factorial Structure for Riso-Hadson Enneagram Test Indicator”. Journal Of Educational and Psychological Researches 13, no. 50 (July 3, 2016): 30–62. Accessed May 7, 2025. https://jperc.uobaghdad.edu.iq/index.php/jperc/article/view/341.