Frolik, Lawrence A.
West Publishing , 2010
Buku Teks
Foster, Nigel
Oxford Univesity Press, 2008
Buku Teks
Enzo Cannizzaro, editor
Oxford University Press, 2011
Buku Teks
Chandos , 2013
eBooks
Berman, Paul Schiff, 1966-
Cambridge University Press, 2012
Buku Teks