Jones, David J., author
Australia, Second Back Row Press
Buku Referensi
Oxford University Press, 1996
Buku Referensi
Jones, David J.
Second Back Row Press, 1981
Buku Teks
Paxton, John, author
J.M. Dent & Sons, 1992
Buku Referensi
Brown, Wendy E., author
McGraw-Hill, 1993
Buku Referensi