Feng, Bang-Yan, author
Cengage Learning, 2012
Buku Teks
Passmore, John, author
Gerald Duckworth, 1957
Buku Teks
Passmore, John, author
Penguin Books, 1972
Buku Teks SO
Penniman, T.K.
Duckworth, 1935
Buku Teks
Smellie, Kingsley Bryce, 1897-1987
Gerald Duckworth & Co,LTD, 1950
Buku Teks