APA-referens (7:e uppl.)

Fredrickson, B. (2009). Positivity (First edition.). Three Rivers Press.

Chicago-referens (17:e uppl.)

Fredrickson, Barbara. Positivity. First edition. New York: Three Rivers Press, 2009.

MLA-referens (9:e uppl.)

Fredrickson, Barbara. Positivity. First edition. Three Rivers Press, 2009.