Lua APA (7ú heag.)
ebrary, Inc, Emmons, R. A., & McCullough, M. E. (2004). The psychology of gratitude. Oxford University Press.
Lua i Stíl Chicago (17ú heag.)
ebrary, Inc, Robert A. Emmons, agus Michael E. McCullough. The Psychology of Gratitude. Oxford ; New York: Oxford University Press, 2004.
Lua MLA (9ú heag.)
ebrary, Inc, et al. The Psychology of Gratitude. Oxford University Press, 2004.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.