Wright, Charles Robert, author
New York, N.Y. Random House 1966,
Buku Teks
Jossey-Bass, 1968
Buku Teks
Berlin, Normand
Macmillan Education, 1988
Buku Teks
Griffin, Ricky W., author
Addison-Wesley, 1995
Buku Teks
Griffin, Ricky W., author
Prentice-Hall, 2002
Buku Teks