Williams, J. D.
Little, Brown and Co., 1980
Buku Teks
Seeley, Harry W.
W.H. Freeman, 1972
Buku Teks
Giles, J. P.
Rigby, 1962
Buku Teks
McGivering, Ian C.
Liverpool University Press, 1960
Buku Teks
Batten, J.D.
D.B. Taraporevala Sons & Co., 1963
Buku Teks