Gibson, James L.
Irwin, 1997
Buku Teks
Dale, Ernest
New York, N.Y., American Management Association
Buku Teks
Dale, Ernest
American Management Association, 1955
Buku Teks
Ritchie, J.B.
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Buku Teks
Pfifner, John M.
Prentice-Hall, 1960
Buku Teks