Whitford, Harold C.
Regents Publishing, 1973
Buku Teks
Corder, Jim W., author
Scott, Foresman and Company, 1981
Buku Referensi
Schiffhorst, Gerald J., author
McGraw-Hill, 1991
Buku Referensi
Maimon, Elaine P., author
McGraw-Hill, 2012
Buku Referensi
Wilson, Kevin, 1958- , author
American Management Association;, 2010
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