Mortenson, Greg, author
Hikmah, 2009
Buku Teks
Pak Wanseo
Seoul : Jimoondang Publishing Company, 2004
Buku Teks
Foreign Languages Publishing, [date of publication not identified]
Buku Teks
Mallan, Lloyd, author
Prentice-Hall, 1964
Buku Teks
Ha, Tae Hung, author
Yonsei University Press, 1984
Buku Teks