Nara, Hiroshi, 1951-
University of Hawai Press, 2003
Buku Teks SO
Wilkes, Angela
Passport Books, [Date of publication not identified]
Buku Teks SO
The National Institute of the Korean Language & The International Korean Language Foundation, 2008
Buku Teks
Verbruggen, Katja
Coutinho, 2013
Buku Teks
Bruce, R. Robert
Hodder & Stoughton, 1994
Buku Teks