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Data reduction : analysing and interpreting statistical data
Ehrenberg, Andrew S. C., (1975)
Basic statistical methods
Downie, N. M., (1965)
Statistics : an introduction
Rickmers, Albert D., (1967)
Mathematical statistics
Freund, John E., (1980)
Mathematical Statistics
Freund, John E., (1965)
Modern business statistics
Freund, John E., (1958)