Shinn, George
McGraw-HIll , 1986
Buku Teks
Kouzes, James M., author
Jossey-Bass, 2002
Buku Teks
Cadwell, Charles M., author
[American Management Association, ], 2004
eBooks
Jennings, Eugene E.
McGraw-Hill, 1960
Buku Teks
Kouzes, James M., author
Erlangga, 2004
Buku Teks