1. Bock, R. D. (1975). Multivariate Statistical Methods in Behavioral Research. New York: McGraw-Hill.
2. Browne, E. T. (1958). Introduction to the Theory of Determinants and Matrices. Chapel Hill, N.C.: The University of North Carolina Press.
3. Cronbach, L. J. (1951). Coefficient alpha and the internal structure of tests. Psychometrika, 16, 297–334.
4. Graybill, F. A. (1961). An Introduction to Linear Statistical Models. New York: McGraw-Hill.
5. Graybill, F. A. (1969). Introduction to Matrices with Applications in Statistics. Belmont, California: Wadsworth Publishing Company.