Ko, Jong-sok
Guko ui phunggyeongdel : Ko Jong-sok ui urimal gangchaw = language of landscapes: Chong-sŏk Ko's Korean classes
Munhak gawajiseongsa, 2007
Buku Referensi
Ko, Chong-sok, 1959-
Maltul ui punggyong : Ko Chong-sok ui Hangugo sanchaek
Kaema Kowon, 2007
Buku Teks
U ko ko
Approaches and endeavours for health, vol.2/ U Ko Ko
SEARO, 1991
Buku Teks
Saroso Wirodihardjo
Ko-operasi dan masalah batik
GKBI, 1954
Buku Teks
Yi, Kwang-ho, 1963 May 23-
Ingmyong ui sarang
Munhak kwa Chisongsa , 2009
Buku Teks