21 segi chŏnmang kwa taechʻaek
By: [pʻyŏnjip Illyu Sahoe Chaegŏn Yŏnʼguwŏn].
Publisher: Kyŏnghŭi Taehakkyo Chʻulpʻanʼguk
Published: 1982
Language: kor
Number of pages: 376