Creighton, Donald
Macmillan, 1952-1955
Buku Teks SO
Creighton, Donald
Macmillan, 1956
Buku Teks SO
Butters, J. Keith
Harvard University Press , 1951
Buku Teks
Hy, Ronald John
Greenwood Press, 1995
Buku Teks
Barnes, John A.
American Management Association, 2005
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