Cropp, John Anthony David
John Wiley & Sons Ltd., 1970
Buku Teks
Bloxam, GA
Gower Press, 1972
Buku Teks
Manchester, Colin, author
Routledge.Cavendish, Taylor & Francis Group, 2008
Buku Teks
Meinhardt, Peter, author
Gower Press, 1971
Buku Teks
Campbell, Don G., 1946-, author
MAcDonald and Evans , 1978
Buku Teks