Hoffer, Jeffrey A., author
Addison-Wesley, 1998
Buku Teks
Hoffer, Jeffrey A., author
The Benyamin/cummings pub, 1996
Buku Teks
Hawryszkiewycz, Igor Titus, author
Prentice-Hall, 1994
Buku Teks
Edwards, Perry
Mitchell McGraw-Hill , 1993
Buku Teks
Cutts, Geoff, author
Alfred Waller, [date of publication not identified]
Buku Teks