Creswell, John W., author
SAGE Publications, 2018
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Creswell, John W., author
Sage, 1998
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Neuman, William Lawrence, 1950-, author
Allyn and Bacon, 2003
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Punch, Keith F., author
SAGE Publications, 1998
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Palys, T.S. (Theodore Stephen), author
Nelson Education, 2014
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