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Wadsworth, 2009
Buku Teks
Bardes, Barbara A., author
Thomson/Wadsworth, 2006
Buku Teks
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Polity Press, 2002
Buku Teks
edited by Stephen K. Bailey
United States Information Agency, 1973
Buku Teks
Stephen J. Wayne [et all.]
Thomson, 2005
Buku Teks