Brown, Harold I.
Rationality
Routledge, 1988
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Sen, Amartya, 1933-
Rationality and freedom
Oxford University Press, 2002
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Churchill, Gilbert A.
Marketing research : methodological foundations
The Dryden Press, 1995
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Churchill, Gilbert A.
Marketing research : methodological foundations
Thomson, 2005
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Systems research : methodological problems
edited by J.M. Gvishiani
Pergamon Press, 1984
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