The psychology of gratitude

MLA

Emmons, Robert A. and Michael E. McCullough. The psychology of gratitude. 1st ed. Oxford ; New York : Oxford University Press, c2004.

APA

Emmons, R. & McCullough, M. (2004). The psychology of gratitude. 1st ed. Oxford ; New York : Oxford University Press.

Chicago

Emmons, Robert A. and Michael E. McCullough. The psychology of gratitude. 1st ed. Oxford ; New York : Oxford University Press, c2004.