Chandos , 2013
eBooks
Prasch, Robert E., author
Edward Elgar, 2008
Buku Teks
McGraw-Hill, [date of publication not identified]
Buku Teks
Clinton, Bill, author
Arrow Books, 2008
Buku Teks
Morgan, Mary S., 1952-2011, author
Cambridge University Press, 2012
Buku Teks