TY  - BOOK
AU  - Creswell,John W.
TI  - Research design: qualitative, quantitative, and mixed methods approaches
SN  - 9781412965576
PY  - 2009///
CY  - Thousand Oaks, California
PB  - Sage Publications
KW  - Research  methods
N1  - Includes bibliographical references and index
ER  -