Hough, Michael
Routledge, 1995
Buku Teks
Macmillan , 1980
Buku Teks
Sievert, Thomas
Spon Press, 2003
Buku Teks
Mumford, Lewis
Harcourt, Brace, 1938
Buku Teks
edited by Andrew Blowers, Chris Hammett and Philip Sarre
Hutchinson Educational in association with the Open University Press, 1974
Buku Teks