Cita APA (7a ed.)

Mannheim, H., & Spencer, J. C. (1949). Problems of classification in the English penal and reformatory system. I.S.T.D.

Cita Chicago Style (17a ed.)

Mannheim, Hermann, y John Carrington Spencer. Problems of Classification in the English Penal and Reformatory System. London: I.S.T.D, 1949.

Cita MLA (9a ed.)

Mannheim, Hermann, y John Carrington Spencer. Problems of Classification in the English Penal and Reformatory System. I.S.T.D, 1949.