Cita APA (7th ed.)

Hefferon, K., & Boniwell, I. (2011). Positive psychology: Theory, research and applications. Open University Press/McGraw-Hill.

Cita Chicago (17th ed.)

Hefferon, Kate, i Ilona Boniwell. Positive Psychology: Theory, Research and Applications. Maidenhead, Berkshire ; New York: Open University Press/McGraw-Hill, 2011.

Cita MLA (9th ed.)

Hefferon, Kate, i Ilona Boniwell. Positive Psychology: Theory, Research and Applications. Open University Press/McGraw-Hill, 2011.