The Korea Herald, editor
Jimoondong, 2008
Buku Teks
Finkle, Jason L., author
John Wiley & Sons, 1968
Buku Teks
Finkle, Jason L., author
John Wiley & Sons, 1966
Buku Teks
Arango, E. Ramon
Westview Press, 1978
Buku Teks
edited by Janet Moyles
McGraw-Hill, 2007
Buku Teks