APA (7th ed.) Citation

Hays, P. (1971). New horizons in psychiatry (2. ed.). Penguin Books.

Chicago Style (17th ed.) Citation

Hays, Peter. New Horizons in Psychiatry. 2. ed. Harmondsworth, Middlesex: Penguin Books, 1971.

MLA (9th ed.) Citation

Hays, Peter. New Horizons in Psychiatry. 2. ed. Penguin Books, 1971.