Elliot, Rose
Chapmans Publisher Ltd., 1994
Buku Referensi
Minrath, William R.
D. Van Nostrand, 1956
Buku Teks
Weisman, Roanne
Health Communications, Inc, 2003
Buku Teks
Rogers, Wayne
Amacom, 2011
Buku Teks
Rogers, Wayne, 1933-
[American Management Association, ], 2011
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