Norton, Peter, author
Brady Simon & Schuster , 1990
Buku Teks
Norton, Peter, author
Microsoft Corp., 1985
Buku Teks
Robertson, S. Ian, author
Psychology Press, 2001
Buku Teks
Norton, Peter, author
Brady Pub., 1993
Buku Teks
Fox, William M
Jossey Bass, 1987
Buku Teks