Green, Andy, author
Erlangga, 2004
Buku Teks
Bernays, Edward L., author
University of Oklahoma Press, 1952
Buku Teks
Haywood, Roger, 1939-, author
McGraw-Hill , 1984
Buku Teks
Cutlip, Scott M., author
Indeks, 2005
Buku Teks
Dilenschneider, Robert L., author
American Management Association, 2010
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