Heinerman, John, author
Prentice Hall, Paramus, N.J., 1998
Buku Teks SO
Griffith, H. Winter, author
Fisher Books, 1998
Buku Teks
Minich, Deanna M., author
Conari Press, 2010
Buku Teks
Murray, Michael T., author
Prima Pub., Rocklin, CA., 1994
Buku Teks SO
Murray, Michael T., author
CA Prima, 1995
Buku Teks