Gilley, Jerry W, author
Perseus Books, 2000
Buku Teks
Gilley, Jerry W
Perseus Books, 1999
Buku Teks
Gilley, Jerry W, author
Perseus Books, 2000
Buku Teks
Bennis, Warren G., author
McGraw-Hill, 1966
Buku Teks
Patten, Thomas H., Jr.
John Wiley & Sons, 1981
Buku Teks