Kesebir, P., & Diener, E. (2009). In pursuit of happiness: Empirical answers to philosophical questions. In E. Diener (Ed.), The science of well-being: The collected works of Ed Diener (pp.59-74). Dordrecht, Netherlands: Springer.
Ryan, R. M., & Deci, E. L. (2001). On happiness and human potentials: A review of research on hedonic and eudaimonic well-being. Annual review of psychology, 52, 141-166.