APA (7th ed.) Citation

Elkin, W. A. (1957). The English penal system. Penguin Books.

Chicago Style (17th ed.) Citation

Elkin, Winifred A. The English Penal System. Harmondsworth, Midd: Penguin Books, 1957.

MLA (8th ed.) Citation

Elkin, Winifred A. The English Penal System. Penguin Books, 1957.