Gilmore, Thomas North, author
Jossey Bass, 1988
Buku Teks
Nahavandi, Afsaneh, author
Prentice-Hall, 2000
Buku Teks
Liddle, R. William, author
Allen and Unwin, 1996
Buku Teks
Walsh, Charles V., author
New York, 1977
Buku Teks
edited by Angus McIntyre
Oxford University Press, 1988
Buku Teks