Ingman, Terence
International ist Student Edition, 1998
Buku Teks
Ingman, Terence
Blockstone Press, 1998
Buku Teks
edited by Stephen Clarke
Harper Collins, 1992
Buku Referensi
Korea Foundation
Cookand/Besthome, 2003
Buku Teks
Peters, Pam, author
Cambridge University Press, 2006
Buku Referensi