Chuch'e ŭmak yesul kyoyuksa e kiri pinnal pulmyŏl ŭi ŏpchŏkTong-uk Yi · First published 2017Open the Tome
Hanʼguk hyŏndae si yŏnʼguSin, Tong-uk, Yŏl-gyu Kim, Sang-tʻaek Yi · First published 1977Open the Tome
Anbo tʻongil munje kibon charyojip ; pu, Topʻyo mit yŏnpʻyoTong-uk Yi · First published 1971Open the Tome