Moore, W.G.
London : Penguin Books, 1984,
Buku Referensi
Hall, Tim, 1968-, author
Routledge, 2018
Buku Teks
Zheng, Ping, author
China Intercontinental Press, 2010
Buku Teks
edited by Otis W. Freeman and John W. Morris
McGraw-Hill, 1958
Buku Teks
Freeman, Otis W., author
John Wiley & Sons, 1951
Buku Teks