O, Song-un
Darakwan, 2009
Buku Teks
O, Song-un
Darakwan, 2009
Buku Teks
The National Institute of the Korean Language & The International Korean Language Foundation, 2008
Buku Teks
In, Ku Kim-Marshall
Hankookmunhwasa, 2006
Buku Teks
Wu, Hyong-sik
Language Plus, 2007
Buku Teks