Beker, Jerome, and Reuven Feuerstein. “Toward a Common Denominator in Effective Group Care Programming: The Concept of the Modifying Enviornment”. Journal of Child and Youth Care Work 7 (March 1, 1991): 20–30. Accessed April 19, 2024. http://acycpjournal.pitt.edu/ojs/jcycw/article/view/179.