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Wlley, 2016
Buku Teks
Duncan, Peter, author
Sage, 2014
Buku Teks
Du Mas, Mark M., author
MdM Books, 2010
Buku Teks
Chatterjee, Margareth, author
Council for Research in Values and Philosophy , 2007
Buku Teks
Humana Press, 1995
Buku Teks