Humphrey, Thomas J., author
John Wiley & Sons, 1978
Buku Teks
Drew, Rodney
Gower, 1987
Buku Teks
Holmes, B.J., author
DP Publication Ltd., 1985
Buku Teks
Snover, Stephen L., author
Prentice-Hall, 1982
Buku Teks
Catlin, Avery, author
Prentice-Hall, 1992
Buku Teks