Walters, Brenda L., author
Upper Saddle River Prentice Hall , 1996
Buku Teks
Einstein, David, author
McGraw-Hill, 1996
Buku Teks
Crumlish, Christian, author
McGraw-Hill , 1996
Buku Teks
by Frank Minirth [and others]
Moody Press, 1990
Buku Teks
Einstein, David
Berkeley, Calif.: McGraw-Hill, 1996,
Buku Referensi