Blanchard, Benjamin S., author
Prentice-Hall, 1990
Buku Teks
Dennis, Alan, 1951-, author
John Wiley & Sons, 2005
Buku Teks
Edwards, Perry
Mitchell McGraw-Hill , 1993
Buku Teks
Cutts, Geoff, author
Alfred Waller, [date of publication not identified]
Buku Teks
Dewitz, Sandra Donaldson, author
McGraw-Hill, 1996
Buku Teks