Epstein, Jennifer Cody
Viking, 2008
Buku Teks
Painter, Clare
OXford University Press, 1989
Buku Teks
Burris, Jon, author
Foreign Languages Press, 2010
Buku Referensi
Burris, Jon, author
Foreign Languages Press, 2010
Buku Teks
Cody, William J.
Prentice-Hall, 1980
Buku Teks