Johnson, Janet Buttolph, 1950-
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Buku Teks
edited David Marsh and Gerry Stoker
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Buku Teks
Evera, Stephen van
Cornell University Press, 1997
Buku Teks
Le Roy, Michael K.
Wadsworth and Cengage Learning, 2013
Buku Teks
Baglione, Lisa A.
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Buku Teks