GOETHE INSTITUT,
Majalah, Jurnal, Buletin
The Korea Foundation.
The Korean Foundation, 1994
Buku Referensi
Carroll, John B., author
Prentice-Hall, 1964
Buku Teks
edited by Richard S. Beal and Jacob Korg
Prentice-Hall, 1966
Buku Teks
edited by Edward A. Feigenbaum, Julian Feldman
McGraw-Hill, 1964
Buku Teks