Pessin, Allan H., author
Business One Irwin, 1990
Buku Referensi
Adler, Bill, author
Jones-Irwin, 1985
Buku Teks SO
Johns, Dean, author
Strategic Information and Research Development Centre , 2010
Buku Teks
Ripley, William Z.
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Buku Teks
Crabb, Peter R., author
McGraw-Hill, 2003
Buku Teks