Smith, Kenneth, author
Pitman, 1975
Buku Teks
Mayson, Stephen W., author
Blackstone Press Limited, 1996
Buku Teks
Gower, L.C.B.
Stevens , 1957
Buku Teks
Gower, L.C.B.
Stevens and Sons, 1969
Buku Teks
Mayson, Stephen W.
Blackstone Press Limited, 1989
Buku Teks