Tŭk-ch'un Yi

1938

• Chosŏnŏ ŏnŏ yŏksa yŏnʼgu
• Chosŏnŏ paltalsa
• Su cheng Chaoxian yu zi xue du ben
• Uri minjogŏ ŭi yŏnʾgu wa chŏnpʻa