Vesterman, William, author
[publisher not identified], [date of publication not identified]
Buku Teks
edited by Andrew Blowers, Bob Evans
Routledge, 1997
Buku Teks
Ward, Ralph D.
John Wiley & Sons, 1997
Buku Teks
Yablonsky, Lewis, author
Wadsworth, 2000
Buku Teks
Nugent William R., author
Thomson Learning, 2001
Buku Teks