1. Aiken, L. S., & West, S. G. (1991). Multiple regression: Testing and interpreting interactions. Newbury Park: Sage.
2. Alber, J., Anderson, R., Delhey, J., Domansky, H., Fahey, T., Keck, W., Maitre, B., Nauenburg, R., Olagnero, M., Ostrowska, A., Saraceno, C., & Whelan, C. (2004). Quality of life in Europe. First results of a New Pan-European survey. Luxembourg: Office for Official Publications of the European Communities.
3. Argyle, M. (1999). Causes and correlates of happiness. In D. Kahnemann, E. Diener, & N. Schwarz (Eds.), Well-being: The foundations of hedonic psychology (pp. 353–373). New York: Russell Sage.
4. Blanchflower, D. G., & Oswald, A. J. (2004). Well-being over time in Britain and the USA. Journal of Public Economics, 88, 1359–1386.
5. Böhnke, P. (2005). First European quality of life survey: Life satisfaction, happiness and sense of belonging. Luxembourg: Office for Official Publications of the European Communities.