Campell, D. T., & Fiske, D. W. (1959). Convergent and discriminant validation by the multitrait-multimenthod matrix. Psychological Bulletin, 56, 81-105.
Campell, D. T., & Fiske, D. W. (1959). Convergent and discriminant validation by the multitrait-multimenthod matrix. Psychological Bulletin, 56, 81-105.