APA (7th ed.) Citation

Frankl, V. E. (1969). The doctor and the soul: From psychotherapy to logotherapy. Penguin.

Chicago Style (17th ed.) Citation

Frankl, Viktor E. The Doctor and the Soul: From Psychotherapy to Logotherapy. Harmondsworth: Penguin, 1969.

MLA (9th ed.) Citation

Frankl, Viktor E. The Doctor and the Soul: From Psychotherapy to Logotherapy. Penguin, 1969.