1. Crystal, D. 1987. The Cambridge Encyclopedia of Language. Cambridge: Cambridge University Press
2. Chung, Y.-H. 1995. An International Language for the World to Come. Journal of Universal Language 1, 56-70
3. Chung, Y.-H. 1996. A Prospect for an International Language in 2045. A Vision 2045, 469-478. Seoul: Sejong Publisher Co
4. Dewey, G. 1971. English Spelling: Roadblock to Reading. New York: Columbia University Press
5. Fishman, J., R. Cooper, & A. Conrad. 1977. The Spread of English. Rowley, MA: Newbury House Publisher, Inc