Northouse, Peter G.
Prentice-Hall, 1985
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edited by Shahe S. Kazarian, David R. Evans
Academic Press, 2001
Buku Teks
edited by Robert Berkow
Merck Sharp & Dohme Research Laboratories, 1987
Buku Teks
Rubenstein, David
Erlangga, 2007
Buku Teks
editor, Patrick Davey ; penerjemah, Annisa Rahmalia
Erlangga, 2005
Buku Teks