APA (7th ed.) Citation

Deci, E. L., & Flaste, R. (1996). Why we do what we do: Understanding self-motivation. Penguin Books.

Chicago Style (17th ed.) Citation

Deci, Edward L., and Richard Flaste. Why We Do What We Do: Understanding Self-motivation. New York [etc.]: Penguin Books, 1996.

MLA (9th ed.) Citation

Deci, Edward L., and Richard Flaste. Why We Do What We Do: Understanding Self-motivation. Penguin Books, 1996.