LoCicero, Joe, author
Adams Media, 2007
Buku Teks
Andrews, Patricia Hayes, author
Waveland, 1986
Buku Teks
Angell, Pamela, author
McGraw-Hill Irwin, 2007
Buku Teks
Thill, John V., author
McGraw-Hill, 1993
Buku Teks
O`Hair, Dan, author
Allyn and Bacon, 2011
Buku Teks