Fisk, Peter, author
Elex Media Komputindo, 2006
Buku Teks
by Roger A. Kerin ... [and others]
McGraw-Hill, 2002
Buku Teks
Etzel, Michael J., author
McGraw-Hill, 2004
Buku Teks
Kurtz, David L., author
The Dryden Press , 1981
Buku Teks
Phillips, Charles F., author
Boston , Houghton Mifflin
Buku Teks