Linneman, Robert E.
Prentice-Hall, 1980
Buku Teks
edited by David W. Ewing
Harper & Brothers, 1958
Buku Teks
Pergamon Press, 1983
Buku Teks
Jones, Harry, 1911-, author
Gower Press , 1974
Buku Teks
Johnston, Robert E., author
American Management Association, 2003
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