Cambridge University Press, 2019
eBooks
editor, Kanishka Jayasuriya
Routledge , 2008
Buku Teks
Bainbridge, Stephen M.
Oxford University Press, 2012
Buku Teks
Finer, S. E.
Clarendon Press Oxford, 1995
Buku Teks
Andrews, William G.
D.van Nostrand Company,Inc., 1968
Buku Teks