5.
Campbell, J. D., Trapnell, P. D., Heine, S. J., Katz, I. M., Lavallee, L. F., & Lehman, D. R. (1996). Self-concept clarity: measurement, personality correlates, and cultural boundaries. Journal of Personality and Social Psychology, 70, 141-156. DOI: 10.1037/0022-3514.70.1.141.