Richmond, I.A., author
Penguin Books, 1955
Buku Teks
Heinemann Educational Books , 1973
Buku Teks
Mackenzie, W.J.M.
Longmas, Green and Co, 1957
Buku Teks
Robson, R., author
Macmillan, 1957
Buku Teks
Chapman, Richard A., author
Constable, 1970
Buku Teks