Duffy, Helen
Cambridge University Press, 2015
Buku Teks
Wittes, Benjamin.
Penguin Press, 2008.
Buku Teks
Charles Webel and Mark Tomass, editors
Routledge, Taylor & Francis Group, 2017
Buku Teks
Herman, Susan N.
Oxford Univesity Press, 2011
Buku Teks
Ali Muhammad
The Phinisi Press, 2015
Buku Teks