edited by Anthony Milner and Mary Quilty
Oxford University Press, 1997
Buku Teks
Minkov, Michael, author
Sage, 2013
Buku Teks
Finer, S. E.
Clarendon Press Oxford, 1995
Buku Teks
by Jack Bavington
Maclean-Hunter Learning Materials, 1976
Buku Teks
Downs, James F., author
Glencoe Press, 1975
Buku Teks