Dyer, Justin Buckley, author
Cambridge University Press, 2013
eBooks
Mason, Diana J., author
Saunders Elsevier, 2002
Buku Teks
Gellhorn, Ernest, author
West , 1994
Buku Teks
Gellhorn, Ernest, author
West, 2004
Buku Teks
Calvani, Terry, author
Little, Brown, 1988
Buku Teks