APA Style

Ph.D., G, P, P, A, P, L. (2013). Code to Joy: the four-step solution to unlocking your natural state of happiness . New York: HarperCollins.

MLA Style

Ph.D., George, Pratt,, Ph.D.,, And, Peter, Lambrou,. "Code to Joy: the four-step solution to unlocking your natural state of happiness". New York: HarperCollins, 2013. BOOKS.