Huntley, James R., author
NATO Information Service, 1972
Buku Teks
New York: W.W.Norton & Company, 1988,
Buku Referensi
Cho, Hae-il, author
Dong-su-Munhak-sa, 1990
Buku Teks
Petrides, George A., author
Houghton Mifflin, 1988
Buku Teks
Fishkin, Rand, author
Penguin, 2018
Buku Teks