Motivation and market behavior / edited by Robert Ferber and Hugh G. Wales
Richard D. Irwin, Inc. , 1958
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Armitage, P.
Statistical methods in medical research
Blackwell Scientific Publication, 1985
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Fisher, Ronald A.
Statistical methods for research workers
Hafner Press, 1970
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Lehmann, Donald R.
Market research and analysis
Richard D. Irwin, 1989
 Buku Teks
Lehmann, Donald R.
Market research and analysis
Richard D. Irwin, 1979
 Buku Teks