McNeill, Patrick
Research methods
Routledge, 1999
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White, Theresa L.
Research methods
Wadsworth and Cengage Learning, 2013
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Leavitt, Fred
Research methods for behavioral scientists
C. Brown Publishers, 1991
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Research methods: guidance for postgraduates
edited by Tony Greenfield
Arnold , 1996
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Gillham, Bill
Case study research methods
Continuum , 2000
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