Claxton, john, author
Glorier International, 1999
Buku Referensi
Paulson, Edward, author
Prenada Media, 2003
Buku Teks
Hilliard, Brooks L., author
Dow Jones-Irwin , 1984
Buku Teks
Monk, Keith, author
McGraw-Hill, 1989
Buku Teks
Lockett, David M.
NTC Business Books, 1989
Buku Teks