Reiner, Laurence E., author
Prentice-Hall, 1972
Buku Referensi
edited by James J. O'Brien, Robert G. Zilly
McGraw-Hill, 1971
Buku Referensi
Levitt, Joel, author
Industrial Press, Inc., 2009
Buku Teks
Sikich, Geary W., author
McGraw-Hill, 1996
Buku Referensi
edited by Paul C. Dinsmore, Jeannette Cabanis-Brewin
American Management Association, 2006
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