edited by Robert M. Maclean
[Publisher not identified], [Date of publication not identified]
Buku Teks SO
Shaw, Josephine
Macmillan, 1993
Buku Teks SO
Paxton, John
Macmillan, 1976
Buku Referensi
Groves, Peter J.
Cavendish, 1995
Buku Teks
Cuthbert, Mike
Cavendish Publishing Limited, 1993
Buku Teks