edited by Ronald P. Grelsamer and Suzanne Loebl
Macmilan , 1996
Buku Referensi
Wilson, Kenneth G., author
Columbia University Press, 1993
Buku Referensi
Benn, Alec
American Management Associations, 1978
Buku Teks
edited by William Wels
Lippincott Williams & Wilkins, 2003
Buku Teks
Berges, Steve, author
American Management Association, 2006
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