Legge, John D., author
Allen Lane The Penguin Press, 1972
Buku Teks
Brecher, Michael
Oxford University Press, 1959
Buku Teks
Legge, John D., author
Penguin Books, 1973
Buku Teks
Economist Books, 1991
Buku Referensi
Karsh, Efraim, author
Free Press, 1994
Buku Referensi