1. Belsley, D.A., Kuh, E., and Welsch, R.E. (1980) Regression Diagnostics: Identifying Influential Data and Sources of Collinearity, Wiley, New York.
2. Golub, G.H. and Van Loan, C.F. (1983) Matrix Computations, Johns Hopkins University Press, Baltimore.
3. Sargan D. (1988) Lectures on Advanced Econometric Theory, Blackwell, New York.
4. Stewart, G.W. (1973) Introduction to Matrix Computations, Academic Press, New York.