Magnusson, Eva
Doing interview-based qualitative research : a learner's guide
Cambridge University Press, 2015
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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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Smith, H.W.
Strategies of social research : the methodological imagination
Prentice-Hall, 1981
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