Shattock, Joanne, author
Oxford University Press, 1993
Buku Referensi
editor, Cecil Turner
Best Western, 1980
Buku Referensi
Cambridge Hobsons 1987
Buku Referensi
Muinzer, Genevieve, author
Routledge and Kegan Paul, 1987
Buku Teks
Habson, 1986
Buku Teks