[publisher not identified], 2008
Buku Teks
Seo Kang-soo, Korean Culture and Information Service,
Majalah, Jurnal, Buletin
Seoul [publisher not identified] 2003,
Buku Teks
Chung, Kyung Cho
Macmillan, 1961, 1956
Buku Teks
Kim, Hak-Joon
Seoul National University Press, 1977
Buku Teks