Lamont, Douglas
Blackwell Publishers, 1996
Buku Referensi
Elex Media Komputindo, 1994
Buku Teks
by Roger A. Kerin ... [and others]
McGraw-Hill, 2002
Buku Teks
Etzel, Michael J.
McGraw-Hill, 2004
Buku Teks
Kurtz, David L.
The Dryden Press , 1981
Buku Teks