1. Growth of the idea of law in adolescence;Adelson;Developmental Psychology,1969
2. Al-Falaij, A. (1991). Family conditions, ego development, and sociomoral development in juvenile delinquency: A study of Bahraini adolescents. Unpublished doctoral dissertation, University of Pittsburgh, PA.
3. Al-Ghamdi, H. H. (1994). The relationship between moral reasoning and ego development in college men and women in Saudi Arabia. Unpublished doctoral dissertation. University of Pittsburgh, PA.
4. Children’s conceptions and displays of moral emotions;Arsenio,2006
5. A comparative study of moral development of Korean and British children;Baek;Journal of Moral Education,2002