Cita APA

Baumgardner, S. R., & Crothers, M. K. (2009). Positive psychology. Prentice Hall.

Chicago Edition Citation

Baumgardner, Steve R., i Marie K. Crothers. Positive Psychology. Upper Saddle River, N.J.: Prentice Hall, 2009.

Cita MLA

Baumgardner, Steve R., i Marie K. Crothers. Positive Psychology. Prentice Hall, 2009.