Title: 15-segi huban-17-segi ch'oban Chosŏnŏ ŭi yŏksajŏk pyŏnhwa yŏn'gu
Subjects: Tusi ŏnhae, Korean language, Pullyu Tu Kongbu si ŏnhae
Time periods: 1500-1894, Middle Korean, 935-1500