1-4 of 4 Books
Unyong-jon
By Michael J. Pettid
Unyŏng chŏn
By Chae-yŏng So,Hong-jae Chang
Unyŏng chŏn ŭi pigyo munhakchŏk yŏn'gu
By Yong-o Chŏn
Unyŏng chŏn. Sugyŏng nangja chŏn
By Il-lyŏl Kim