Topham, Alfred F.
Stevens and Sons, Limited, 1933
Buku Teks
Ivamy, E.R. Hardy, author
Butterworth, 1978
Buku Teks
Farrar, Harry, author
The Donnington Press, 1970
Buku Teks
Smith, Kenneth, author
Pitman, 1975
Buku Teks
Mayson, Stephen W., author
Blackstone Press Limited, 1996
Buku Teks