Powers, E., & Witmer, H. (1951). An experiment in the prevention of delinquency: The Cambridge-Somerville Youth Study. Columbia University Press.
Lua i Stíl Chicago (17ú heag.)Powers, Edwin, agus Helen Witmer. An Experiment in the Prevention of Delinquency: The Cambridge-Somerville Youth Study. New York: Columbia University Press, 1951.
Lua MLA (9ú heag.)Powers, Edwin, agus Helen Witmer. An Experiment in the Prevention of Delinquency: The Cambridge-Somerville Youth Study. Columbia University Press, 1951.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.