For example, F. C. Ridel's Grammaire Coréenne published in 1881. https://imgur.com/oSxewU0 Also, Independence Newspaper(獨立新聞), the nation's first Korean-only newspaper in 1896. https://imgur.com/7bruwF7
kostat.go.kr
"2015년 인구주택총조사 전수집계결과 보도자료" [Results of the 2015 Census of Population and Housing survey]. Korean Statistical Information Service. สืบค้นเมื่อ 28 May 2019.