National Conference on Parole Washington, D.C., & Bell, M. (1957). Parole in principle and practice. National Probation and Parole Association.
Παραπομπή σε μορφή Chicago (17η εκδ.)National Conference on Parole Washington, D.C., και Marjorie Bell. Parole in Principle and Practice. New York: National Probation and Parole Association, 1957.
Παραπομπή σε μορφή MLA (8th εκδ.)National Conference on Parole Washington, D.C., και Marjorie Bell. Parole in Principle and Practice. National Probation and Parole Association, 1957.
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