Liberty, Jesse, author
O'Reilly, 2008
Buku Teks
Hughes, Joan K., author
John Wiley & Sons, 1979
Buku Teks
Brailsford, D.F., author
Ellis Horwood, 1979
Buku Teks
Downes, Valerie A., author
Prentice-Hall, 1982
Buku Teks
Holt, R.C., author
Reston Publishing, 1980
Buku Teks