Lawhorne, Clifton O.
Southern Illinois University Press, 1971
Buku Teks
Perry, Michael J.
Oxford University Press, 1997
Buku Teks
Forer, Lois G.
Norton, 1987
Buku Teks
Greenberg, Daniel S.
The University of Chicago Press , 1999
Buku Teks
Merritt, Davis
[American Management Association;, ], 2005
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