Παραπομπή σε μορφή APA (7η εκδ.)

хThe иNational Association of Social Workers, Karls, J. M., & Wandrei, K. E. (1994). Person in environment system: The PIE classification system for social functioning problems. The National Association of Social Workers.

Παραπομπή σε μορφή Chicago (17η εκδ.)

хThe иNational Association of Social Workers, James M. Karls, και Karin E. Wandrei. Person in Environment System: The PIE Classification System for Social Functioning Problems. Washington: The National Association of Social Workers, 1994.

Παραπομπή σε μορφή MLA (8th εκδ.)

хThe иNational Association of Social Workers, et al. Person in Environment System: The PIE Classification System for Social Functioning Problems. The National Association of Social Workers, 1994.