Marshall, Catherine
Designing qualitative research
Sage, 1999
Buku Teks SO
Viswanathan, Madhu
Measurement error and research design
Sage, 2005
Buku Teks SO
Sjoberg, Gideon
A methodology for social research
Harper & Row, 1968
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Lee, Raymond M.
Unobtrusive methods in social research
Open University Press, 2000
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Methodology of social science research
edited by Sugata Dasgupta
Impex India, 1967
Buku Teks SO