Quigley, Marian, author
IRM Press, 2005
Buku Teks
Routledge, 2004
Buku Teks
Johnson, Rob, author
Jones & Bartlett Learning, 2015
Buku Teks
edited by Joseph DiRenzo III; Nicole K. Drumhiller; and Fred S. Roberts.
DC Westphalia Press, an imprint of the Policy Studies Organization, 2017
Buku Teks
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